ListBox SelectValue is null and selectindex = -1 - c#

The listbox populates but can't find the selected value. It's either null or the default value (first item). Whenever I select another item, it changes to null. I did the !ispostback but still nothing. Using a wizard in asp.net/c#/sql. Any help is appreciated.
protected void Page_Load(object sender, EventArgs e)
{
ListBox lstService = (ListBox)Wizard1.FindControl("lstService");
string s = lstService.SelectedValue.ToString();
int s1 = lstService.SelectedIndex;
if (s == "MarketTrack Toys")
{
Wizard2.Visible = true;
}
if (!Page.IsPostBack)
{
BindGrid();
}
if ((Wizard1.ActiveStepIndex <= 5) && (Wizard1.ActiveStepIndex != 0))
{
Wizard1.DisplaySideBar = true;
Wizard2.DisplaySideBar = false;
}
else
{
Wizard1.DisplaySideBar = false;
Wizard2.DisplaySideBar = true;
}
}
private void BindGrid()
{
dAS = new DataAccessClass();
DataSet ds = new DataSet();
DataTable dt = new DataTable();
ds = dAS.func_FillDataset("select servicename from dbo.Services", "Services");
ListBox lstService = (ListBox)Wizard1.FindControl("lstService");
lstService.DataSource = ds;
lstService.DataTextField = "ServiceName";
lstService.DataValueField = "ServiceName";
lstService.DataBind();
if (lstService.Items.Count > 0)
{
lstService.SelectedIndex = 0;
}
}

Walk it through in a debugger.
Whatever Object that is being placed in the ListBox doesn't know to convert itself to the string you're looking for with ToString()
The ListBox populates correctly because you specify how to get the names with lstService.DataTextField = "ServiceName";
You may have to rework the object you're putting in the ListBox or just override to ToString for that object instead.

Related

how to unbind checkbox List Or Remove checkbox list item in c#.?

this is my code i want to clear my checkbox list because every text change event i'm getting new data from db.
private void txt_search_TextChanged_1(object sender, EventArgs e)
{
fill_check();
}
private void fill_check()
{
src.fun_search = txt_search.Text;
try
{
DataTable dt_pro_name = db.findproduct_name(src);
src.fun_search = null;
if (dt_pro_name.Rows.Count > 0)
{
src.fun_search = dt_pro_name.Rows[0]["id"].ToString();
DataTable ds = db.addcombo(src);
if (ds.Rows.Count > 0)
{
imei.DataSource = ds;
imei.ValueMember = "imei";
}
}
}
catch (Exception ex)
{
}
}
Please tell me whats wrong in my code

Trouble Getting DataGridView to Work with ComboBox Dropdown

I need some help getting my code to work. DataGridView is proving much more complex that I had anticipated. I need someone to please show me how to fix my code, so that both the DataGridView control can be updated and my DataGridViewComboBoxColumn dropdown and DataGridViewCheckBoxColumn controls all work. I'm okay with any strategy, provided the solution you offer is somewhat elegant and complete. I've already spent far too much time trying to figure this out on my own. Any thoughts or suggestions would be greatly appreciated.
Here is a simplifcation of what my backend looks like:
MySqlDataAdapter dataAdapter = new MySqlDataAdapter(sqlRequestString, this.dbConnection);
MySqlCommandBuilder commandBuilder = new MySqlCommandBuilder(dataAdapter);
DataTable table = new DataTable();
table.Locale = System.Globalization.CultureInfo.InvariantCulture;
dataAdapter.Fill(table);
bindingSource.DataSource = table;
If I get rid of the BindingSource, how do I connect the DataTable directly to the DataGridView, so that the ComboBox and Checkbox columns are properly populated?
UPDATE
This should be a complete overview of how I am attempting to initialize my DataGridView:
private void InitializeComponent()
{
/* ... */
this.dataGridView1.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
this.DataGridViewColumn_Section,
this.DataGridViewColumn_Indent,
this.DataGridViewColumn_Content,
this.DataGridViewColumn_Summary,
this.DataGridViewColumn_Role,
this.DataGridViewColumn_Author,
this.DataGridViewColumn_Updated});
this.dataGridView1.Name = "dataGridView1";
this.dataGridView1.DataSourceChanged += new System.EventHandler(this.dataGridView1_DataSourceChanged);
this.dataGridView1.CellEnter += new System.Windows.Forms.DataGridViewCellEventHandler(this.dataGridView1_CellEnter);
this.dataGridView1.CellLeave += new System.Windows.Forms.DataGridViewCellEventHandler(this.dataGridView1_CellLeave);
this.dataGridView1.ColumnAdded += new System.Windows.Forms.DataGridViewColumnEventHandler(this.dataGridView1_ColumnAdded);
this.dataGridView1.SelectionChanged += new System.EventHandler(this.dataGridView1_SelectionChanged);
this.dataGridView1.Leave += new System.EventHandler(this.dataGridView1_Leave);
//
// DataGridViewColumn_Section
//
this.DataGridViewColumn_Section.HeaderText = "Section";
this.DataGridViewColumn_Section.Name = "DataGridViewColumn_Section";
//
// DataGridViewColumn_Indent
//
this.DataGridViewColumn_Indent.HeaderText = "Indent";
this.DataGridViewColumn_Indent.Name = "DataGridViewColumn_Indent";
//
// DataGridViewColumn_Content
//
this.DataGridViewColumn_Content.HeaderText = "Content";
this.DataGridViewColumn_Content.MinimumWidth = 100;
this.DataGridViewColumn_Content.Name = "DataGridViewColumn_Content";
//
// DataGridViewColumn_Summary
//
this.DataGridViewColumn_Summary.HeaderText = "Summary";
this.DataGridViewColumn_Summary.Name = "DataGridViewColumn_Summary";
//
// DataGridViewColumn_Role
//
this.DataGridViewColumn_Role.HeaderText = "Minimum Signoff";
this.DataGridViewColumn_Role.Name = "DataGridViewColumn_Role";
//
// DataGridViewColumn_Author
//
this.DataGridViewColumn_Author.HeaderText = "Author";
this.DataGridViewColumn_Author.Name = "DataGridViewColumn_Author";
this.DataGridViewColumn_Author.ReadOnly = true;
//
// DataGridViewColumn_Updated
//
this.DataGridViewColumn_Updated.HeaderText = "Updated";
this.DataGridViewColumn_Updated.Name = "DataGridViewColumn_Updated";
this.DataGridViewColumn_Updated.ReadOnly = true;
/* ... */
}
public MyWinform()
{
InitializeComponent();
// Initialize DataGridView DataTable
this.dgvDataTable = new DataTable();
// Initialize DataGridView column indexes
this.idxSection = dataGridView1.Columns["DataGridViewColumn_Section"].Index;
this.idxIndent = dataGridView1.Columns["DataGridViewColumn_Indent"].Index;
this.idxContent = dataGridView1.Columns["DataGridViewColumn_Content"].Index;
this.idxSummary = dataGridView1.Columns["DataGridViewColumn_Summary"].Index;
this.idxRole = dataGridView1.Columns["DataGridViewColumn_Role"].Index;
this.idxAuthor = dataGridView1.Columns["DataGridViewColumn_Author"].Index;
this.idxLastUpdate = dataGridView1.Columns["DataGridViewColumn_Updated"].Index;
}
private void MyWinform_Load(object sender, EventArgs e)
{
DataGridView dgv = this.dataGridView1;
DataGridViewComboBoxColumn comboCol;
// Load System Menu
SystemMenu.Load(this.Handle);
// Insert selection prompt
ProcTemplateRecord selectProcPrompt = new ProcTemplateRecord();
selectProcPrompt.PrimaryKey = 0;
selectProcPrompt.ProcName = "Select from the list...";
this.procList.Insert(0, selectProcPrompt);
// Add new procedure prompt
ProcTemplateRecord newProcPrompt = new ProcTemplateRecord();
newProcPrompt.PrimaryKey = -1;
newProcPrompt.ProcName = "Start a new Safe Job Procedure";
this.procList.Add(newProcPrompt);
// Finish initializing the ComboBox dropdown list
this.comboBox1.DataSource = this.procList;
this.comboBox1.DisplayMember = "ProcName";
this.comboBox1.ValueMember = "PrimaryKey";
// Finish initializing DataGridView and bind to BindingSource
this.dataGridView1.AutoGenerateColumns = false;
/*
// Finish initializing the DataGridView ComboBox columns...
comboCol = (DataGridViewComboBoxColumn)dgv.Columns[this.idxSection];
comboCol.DataSource = Enum.GetValues(typeof(SectionType));
comboCol.ValueType = typeof(SectionType);
comboCol.DropDownWidth = ComboBoxMaxLabelWidth(comboCol);
comboCol = (DataGridViewComboBoxColumn)dgv.Columns[this.idxRole];
comboCol.DataSource = Enum.GetValues(typeof(RoleType));
comboCol.ValueType = typeof(RoleType);
comboCol.DropDownWidth = ComboBoxMaxLabelWidth(comboCol);
this.dataGridView1.DataSource = this.dgvDataTable;
*/
this.RefreshDataGridViewColumnWidths();
// Setup post-initialization DataGridViewEvent handlers
this.dataGridView1.CellValueChanged += new System.Windows.Forms.DataGridViewCellEventHandler(this.dataGridView1_CellValueChanged);
this.dataGridView1.CurrentCellDirtyStateChanged += new System.EventHandler(this.dataGridView1_CurrentCellDirtyStateChanged);
}
private void dataGridView1_DataSourceChanged(object sender, EventArgs e)
{
this.RefreshDataGridViewColumnWidths();
}
private void dataGridView1_CellEnter(object sender, DataGridViewCellEventArgs e)
{
DataGridView dgv = (DataGridView)sender;
this.RefreshButtons();
if (e.ColumnIndex == this.idxSection)
{
this.label_dgvToolTip.Visible = false;
}
else if (e.ColumnIndex == this.idxIndent)
{
this.label_dgvToolTip.Visible = false;
}
else if (e.ColumnIndex == this.idxContent)
{
this.label_dgvToolTip.Visible = false;
}
else if (e.ColumnIndex == this.idxSummary)
{
this.label_dgvToolTip.Visible = false;
}
else if (e.ColumnIndex == this.idxRole)
{
this.label_dgvToolTip.Visible = false;
}
else if (e.ColumnIndex == this.idxAuthor)
{
this.label_dgvToolTip.Visible = false;
this.label_dgvToolTip.Text = "Author column values are read only.";
this.label_dgvToolTip.Visible = true;
}
else if (e.ColumnIndex == this.idxLastUpdate)
{
this.label_dgvToolTip.Visible = false;
this.label_dgvToolTip.Text = "Updated column values are read only.";
this.label_dgvToolTip.Visible = true;
}
else
{
this.label_dgvToolTip.Visible = false;
}
this.idxActiveColumn = e.ColumnIndex;
this.idxActiveRow = e.RowIndex;
}
private void dataGridView1_CellLeave(object sender, DataGridViewCellEventArgs e)
{
this.label_dgvToolTip.Visible = false;
this.RefreshButtons();
}
private void dataGridView1_ColumnAdded(object sender, DataGridViewColumnEventArgs e)
{
DataGridView dgv = this.dataGridView1;
if ((e.Column.DataPropertyName == "PageSection") &&
(e.Column.CellType != typeof(DataGridViewComboBoxCell)))
{
var cbo = GetComboBoxColumn(e.Column);
cbo.DataSource = Enum.GetValues(typeof(SectionType));
cbo.ValueType = typeof(SectionType);
dgv.Columns.Remove(e.Column);
dgv.Columns.Add(cbo);
}
else if ((e.Column.DataPropertyName == "UserRole") &&
(e.Column.CellType != typeof(DataGridViewComboBoxCell)))
{
var cbo = GetComboBoxColumn(e.Column);
cbo.DataSource = Enum.GetValues(typeof(RoleType));
cbo.ValueType = typeof(RoleType);
dgv.Columns.Remove(e.Column);
dgv.Columns.Add(cbo);
}
}
private void dataGridView1_SelectionChanged(object sender, EventArgs e)
{
this.RefreshButtons();
}
private void dataGridView1_Leave(object sender, EventArgs e)
{
DataGridView dgv = this.dataGridView1;
if (dgv.SelectedCells.Count == 0)
{
this.idxActiveColumn = -1;
this.idxActiveRow = -1;
}
}
private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
DataGridView dgv = (DataGridView)sender;
DataGridViewComboBoxCell sectionCell = (DataGridViewComboBoxCell)dgv.Rows[e.RowIndex].Cells[this.idxSection];
DataGridViewTextBoxCell indentCell = (DataGridViewTextBoxCell)dgv.Rows[e.RowIndex].Cells[this.idxIndent];
DataGridViewComboBoxCell roleCell = (DataGridViewComboBoxCell)dgv.Rows[e.RowIndex].Cells[this.idxRole];
Int32 colIndex = e.ColumnIndex;
try
{
if (colIndex == this.idxIndent)
{
int number;
string cellValue = indentCell.Value.ToString();
bool isNumeric = int.TryParse(cellValue, out number);
if (!isNumeric)
{
cellValue = cellValue.Substring(0, cellValue.Length - 1);
indentCell.Value = cellValue;
}
}
// Column resizing code goes last
this.RefreshDataGridViewColumnWidths();
this.dgvIsDirty = true;
}
catch (Exception ex)
{
throw new Exception("Failed to refresh DataGridView on cell change.", ex);
}
}
private void dataGridView1_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
DataGridView dgv = (DataGridView)sender;
try
{
if (dgv.IsCurrentCellDirty)
{
// This fires the cell value changed handler below
dgv.CommitEdit(DataGridViewDataErrorContexts.Commit);
this.RefreshDataGridViewColumnWidths();
}
}
catch (Exception ex)
{
throw new Exception("Failed to commit edit of DataGridView cell.", ex);
}
}
This is the code I am using to update my DataGridView contorl:
// Load the data from the database into the DataGridView
this.dbif.GetProcedure(this.procList.ElementAt(selectedIndex).PrimaryKey, ref this.dgvDataTable);
DataRow[] rows = this.dgvDataTable.Select();
//Object dgvDataSource = dgv.DataSource;
//dgv.DataSource = null;
foreach (DataRow dataRow in rows)
{
DataGridViewRow dgvRow = new DataGridViewRow();
dgvRow.CreateCells(dgv);
dgvRow.Cells[idxSection].Value = dataRow.Field<string>(0);
dgvRow.Cells[idxIndent].Value = dataRow.Field<byte>(1);
dgvRow.Cells[idxContent].Value = dataRow.Field<string>(3);
dgvRow.Cells[idxSummary].Value = dataRow.Field<UInt32>(4) != 0;
dgvRow.Cells[idxRole].Value = dataRow.Field<string>(5);
dgvRow.Cells[idxAuthor].Value = dataRow.Field<string>(6) + dataRow.Field<string>(7);
dgvRow.Cells[idxLastUpdate].Value = dataRow.Field<DateTime>(8).ToString();
dgv.Rows.Add(dgvRow);
}
//dgv.DataSource = dgvDataSource;
This is how my enumerations are defined:
public enum SectionType
{
ESJP_SECTION_HEADER = 1, // start with 1 for database compatibility
ESJP_SECTION_FOOTER,
ESJP_SECTION_BODY
}
public enum RoleType
{
ESJP_ROLE_NONE = 1, // start with 1 for database compatibility
ESJP_ROLE_TEST_ENG,
ESJP_ROLE_FEATURE_LEAD,
ESJP_ROLE_TEAM_LEAD
}
There are a number of issues/improvements. There are too many unknowns about the data to fix everything, but some techniques shown here may help.
1. Manually populating the DGV
You ought not have to do that. Just setting the DataTable as the DataSource will work most of the columns.
2. Expressions
You have 2 expressions where you populate the dgv:
dgvRow.Cells[idxSummary].Value = dataRow.Field<UInt32>(4) != 0;
dgvRow.Cells[idxAuthor].Value = dataRow.Field<string>(6) + dataRow.Field<string>(7);
This leads me to believe the dgv is ReadOnly. Otherwise you will have trouble with those. The Summary for instance: if the user Unchecks the column, you can set that value to 0, but what if they check it? How will you know what value to set??
Indent as Byte seems odd too - almost like it is a boolean.
3. Combos
In a previous question, the dgv was populated from a List<Class>. With that as the `DataSource, an Enum works well because the 2 properties were of that Type. With an enum, the following works:
cbo.ValueType = typeof(RoleType);
It's less likely to work with a DataTable as in version 1, 2 or 3 of this question because there is no db/Datatable type of SectionType or RoleType. In other cases where there is a translation - show the user "ESJP_SECTION_HEADER" but store 2 in the DataTable and ultimately the DB - a small NameValue pairs list will work. A different data model means a different approach to the DGV cbo.
It now looks like those are text columns (I've asked 3 times). If so, you really just need to constrain the selection to the enum names. In the IDE, paste in the text for the Items property:
Alternatively, you can do so in code:
private string[] secList = {"ESJP_SECTION_HEADER","ESJP_SECTION_FOOTER",
"ESJP_SECTION_BODY"};
...
((DataGridViewComboBoxColumn)dgv1.Columns["PageSection"]).Items.AddRange(secList);
AutoGenerateColumns
When the DataSource for a DGV is set, by default it will automatically create a DGVcolumn for each DTColumn, and this works well for the most part. Sometimes you'll want some small tweak like hide an Id column, or change a TextColumn to a CBOColumn. Code in the ColumnAddedEvent to make these changes rather than manually laying out columns can work well.
But since there are quite a few such such changes and since you have already layed out columns in the IDE, you want to be sure to set AutoGenerateColumns to false somewhere in code. Otherwise it will add still more columns.
Setup
Things you may or may not have done in the DGV designer:
Add the columns in whatever order you wish, but be sure to assign the DataPropertyName to the name used in the SQL query. Leave it blank for Author.
Expression columns like Author means either changing the query or doing some formatting in the DGV. For this, add First and Last name columns to the DGV as well as the Author column. Make the first two invisible. The code below shows the formatting. (Make sure that the compound column (Author) appears after the parts!).
Normally, I would try to do that in SQL: SELECT (First + Last) AS Author, but if you do not want to mess with that query, you can concat in DGV events.
Be sure to add the names for the Page and Role columns to the Items collection.
Then, the rest is fairly simple:
private DataTable dtF;
...
string SQL = "SELECT PageSection, Indent, Content, SummaryId, "
+ "UserRole, AuthorFirstN, AuthorLastN, LastUpdated FROM FellPage";
using (var dbCon = new MySqlConnection(MySQLConnStr))
using (var cmd = new MySqlCommand(SQL, dbCon))
{
dbCon.Open();
dtF = new DataTable();
dtF.Load(cmd.ExecuteReader());
}
// IMPORTANT!!!
dgv1.AutoGenerateColumns = false;
dgv1.DataSource = dtF;
The formatting event:
private void dgv1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
{
if (dgv1.Rows[e.RowIndex].IsNewRow)
return;
if (e.ColumnIndex == 7) // ie "Author"
{
e.Value = dgv1.Rows[e.RowIndex].Cells[6].Value.ToString() + ", " +
dgv1.Rows[e.RowIndex].Cells[5].Value.ToString();
e.FormattingApplied = true;
}
}
Result:
It is very important to turn off AutoGenerateColumns. By default, the dgv will add columns for everything in the source. Since you added them, set that to false in the code (there is no IDE property for it).
By virtue of Summary and Indent being defined as check columns, it translates non zero as true. I have no idea how you will edit any SummaryId value. That should probably be a text column so they can enter a value, if that is allowed (that col could be read only too?).
My query and such arent as complex as yours, and surely there are some details I/we are unaware of which have been omitted. But there is certainly a much less gyrations and code to get it working...whatever this is.
Being bound to a DataTable, when the user edits anything, the changes flow thru to the underlying DataTable (use the various Validating events to check their work). The DataTable in turn tracks the state of each row - new, changed, deleted - so later you can:
var changes = dtF.GetChanges();
This will return all the rows which have been changed since the last AcceptChanges().

Cannot select specific row on Janus GridEX

So I'm accessing a DB through a stored procedure and am able to pull the data I wanted into a popup box. The problem now is that no matter what row I click on, the SAME data keeps populating my fields. How the heck can I choose a particular row, and have that specific row's data pulled from the DB? Thanks for any help
Form1
public partial class DSC_Mon : Form
{
DSCU_SvcConsumer.MTCaller Caller;
DataSet dsZA;
DataSet dsOut;
public DSC_Mon()
{
InitializeComponent();
Caller = new DSCU_SvcConsumer.MTCaller();
dsZA = new DataSet();
dsOut = new DataSet();
}
private void DSC_Mon_Load(object sender, EventArgs e)
{
timer1.Enabled = true;
}
private void LoadData()
{
if (!dsZA.Tables.Contains("Query"))
{
DataTable dtZA = dsZA.Tables.Add("Query");
dtZA.Columns.Add("str");
dtZA.Rows.Add(string.Format(#"exec MON_GetStatus"));
}
//dtZA.Rows.Add(string.Format(#"select * from am_company"));
dsOut.Clear();
dsOut.Merge(Caller.CallRequest("ZuluAction", dsZA));
if (gridEXMon.DataSource == null)
{
gridEXMon.DataSource = dsOut;
gridEXMon.DataMember = "Table";
}
//gridEXMon.RetrieveStructure();
}
private void timer1_Tick(object sender, EventArgs e)
{
timer1.Enabled = false;
LoadData();
timer1.Enabled = true;
}
private void gridEXMon_DoubleClick(object sender, EventArgs e)
{
ReportInfo report = new ReportInfo();
report.ShowDialog();
}
}
I replaced the private void gridEXMon_DoubleClick with:
private void gridEXMon_RowDoubleClick(object sender, Janus.Windows.GridEX.RowActionEventArgs e)
{
if (e.Row.RowIndex < 0)
return;
int rowIndex = Convert.ToInt32(e.Row.RowIndex);
ReportInfo report = new ReportInfo(rowIndex);
report.ShowDialog();
}
Popup Dialog
public partial class ReportInfo : Form
{
public ReportInfo()
{
InitializeComponent();
DSCU_SvcConsumer.MTCaller caller = new DSCU_SvcConsumer.MTCaller();
DataSet dsZA = new DataSet();
DataSet dsOut = new DataSet();
if (!dsZA.Tables.Contains("Query"))
{
DataTable dtZA = dsZA.Tables.Add("Query");
dtZA.Columns.Add("str");
dtZA.Rows.Add(string.Format(#"MON_ReportInfo"));
}
dsOut.Clear();
dsOut.Merge(caller.CallRequest("ZuluAction", dsZA));
DataTable dt = dsOut.Tables["Table"];
DataRow dr = dt.Rows[0];
if (dt != null)
{
systemNameTextBox.Text = dr["System"].ToString();
contactName1TextBox.Text = dr["Manager"].ToString();
functionNameTextBox.Text = dr["Function"].ToString();
durationMSTextBox.Text = dr["Speed"].ToString();
}
}
I then sent the rowIndex to the popup:
DataTable dt = dsOut.Tables["Table"];
DataRow dr = dt.Rows[rowIndex];
systemNameTextBox.Text = dr["System"].ToString();
contactName1TextBox.Text = dr["Manager"].ToString();
functionNameTextBox.Text = dr["Function"].ToString();
durationMSTextBox.Text = dr["Speed"].ToString();
}
Better to get the data from the grid to save the extra call to the database in your ReportInfo class.
Here is the code:
private void gridEXMon_DoubleClick(object sender, EventArgs e)
{
if (e.Row.RowIndex < 0)
return;
ReportInfo report = new ReportInfo();
String System = Convert.ToInt32(e.Row.Cells["System"].Value);
String Manager = Convert.ToString(e.Row.Cells["Manager"].Value);
String Function = Convert.ToDecimal(e.Row.Cells["Function"].Value);
String Speed = Convert.ToInt32(e.Row.Cells["Speed"].Value);
report.ShowDialog(System, Manager, Function, Speed);
}
Then your ReportInfo class ctor should be:
public partial class ReportInfo : Form
{
public ReportInfo(String System, String Manager, String Function, String Speed)
{
InitializeComponent();
systemNameTextBox.Text = System;
contactName1TextBox.Text = Manager;
functionNameTextBox.Text = Function;
durationMSTextBox.Text = Speed;
}
}
Have you tried with:
gridEXMon.DataSource = dsOut.Tables[0];
// next line is not required if you've already defined proper grid structure
gridEXMon.RetrieveStructure();
Janus has also his own forum available here. You can find there a lot of useful information. For browsing I will use IE. Janus forum works good only with IE...
Edited:
How ReportInfo class can know what record have you selected? Especially that you have fallowing code:
DataTable dt = dsOut.Tables["Table"];
DataRow dr = dt.Rows[0]; // always first record is taken!
Probably you should define ctor with row index:
public ReportInfo(int rowIndex)
{
...
DataTable dt = dsOut.Tables["Table"];
DataRow dr = dt.Rows[rowIndex];
....
}

Keep State of Gridview

I have a gridview and I'm trying to keep the state of. Currently I have it where the user can edit inline( from within the gridview). Regularly I got this working:
protected void GridViewTower_RowEditing(object sender, GridViewEditEventArgs e)
{
//Set the edit index.
GridViewTower.EditIndex = e.NewEditIndex;
//Bind/Re-LoadData data to the GridView control.
LoadData();
Populate();
}
protected void GridViewTower_CancelEditRow(object sender, GridViewCancelEditEventArgs e)
{
//Reset the edit index.
GridViewTower.EditIndex = -1;
//Bind/Re-LoadData data to the GridView control.
LoadData();
Populate();
}
Problem is, I have 3 other features such sorting, dropdown that filters gridview, and a button search which also filters the girdview. When inline editing within any 3 of those modes, I can't control the state in which the gridview is in. Inside my gridview tag, I have both EnableViewState and ViewStateMode set to true.
How can I keep the state of the gridview within these modes?
public void LoadData()
{
if (Session["GridView"] != null)
{
GridViewTower.DataSource = Session["GridView"];
GridViewTower.DataBind();
//Response.Redirect("TowerManagement.aspx"); //
//Session["GridView"] = null;
}
else
{
WISSModel.WISSEntities context = new WISSModel.WISSEntities();
var tower = (from t in context.Towers
where t.isDeleted == false
select new
{
t.TowerId,
t.TowerName,
RangeName = t.Range.RangeName
}).ToList();
GridViewTower.DataSource = tower;
GridViewTower.DataBind();
ViewState["Sort"] = 0;
}
}
protected void Gridview_Sort(object sender, GridViewSortEventArgs e)
{
WISSModel.WISSEntities context = new WISSModel.WISSEntities();
var towers = (from t in context.Towers
where t.isDeleted == false
select new
{
t.TowerId,
t.TowerName,
rangeName = t.Range.RangeName
}).ToList();
DataTable gridviewTable = towers.CopyToDataTable();
gridviewTable.DefaultView.Sort = e.SortExpression + " " + ConvertSortDirectionToSql(e.SortDirection);
GridViewTower.DataSource = gridviewTable;
GridViewTower.DataBind();
Session["GridView"] = GridViewTower.DataSource;
}
You don't need to store whole table in the Session or ViewState. Just store values of SortExpression, SortOrder etc. Here's an example how you can do it.
In my code I have added two private properties to store sortorder and sortexpression:
private string SortOrder
{
get
{
// Toggle order after sorting
string _order = "ASC";//Default
if( ViewState["SortOrder"] != null && ViewState["SortOrder"].ToString() =="DESC")
{
_order = "DESC";
ViewState["SortOrder"] = "ASC";
}
else
{
ViewState["SortOrder"] = "DESC";
}
return _order;
}
set
{
string _order = value.ToLower() == "descending"? "DESC" : "ASC";
ViewState["SortOrder"] = _order;
}
}
private string SortExpression
{
get
{
return ViewState["SortExpression"] != null ? ViewState["SortExpression"].ToString() : "";
}
set
{
ViewState["SortExpression"] = value;
}
}
I have changed your GridView_Sort method to store the sort expression and sort order in newly added properties and called LoadData() method:
protected void Gridview_Sort(object sender, GridViewSortEventArgs e)
{
SortExpression = e.SortExpression;
//Disabled sort direction to enable toggling
//SortOrder = e.SortDirection.ToString();
LoadData();
}
The LoadData() method will be called from many places, whenever we want to load data into GridView. So I have changed it to this:
public void LoadData()
{
WISSModel.WISSEntities context = new WISSModel.WISSEntities();
var towers = (from t in context.Towers
where t.isDeleted == false
select new
{
t.TowerId,
t.TowerName,
rangeName = t.Range.RangeName
}).ToList();
DataTable gridviewTable = new DataTable();
gridviewTable.Columns.Add("TowerId");
gridviewTable.Columns.Add("TowerName");
gridviewTable.Columns.Add("rangeName");
foreach (var t in towers)
{
gridviewTable.Rows.Add(new object[] { t.TowerId, t.TowerName, t.rangeName });
}
if (!String.IsNullOrEmpty(SortExpression))
{
gridviewTable.DefaultView.Sort = String.Format("{0} {1}", SortExpression, SortOrder);
gridviewTable = gridviewTable.DefaultView.ToTable();
}
GridViewTower.DataSource = gridviewTable;
GridViewTower.DataBind();
}
Initially I call the LoadData() method in Page_Load() :
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
LoadData();
}
}
You can download the test project here.

c# databinding modifying grid values

I have a crud form with a datagridview.
Here's my "refresh" code:
private void Recuperar()
{
DataSet ds = new DataSet();
string CommandText = "SELECT * from sectores order by sector";
SQLiteDataAdapter adapter = new SQLiteDataAdapter(CommandText, Variables.Conexion);
DataTable table = new DataTable();
table.TableName = "sectores";
adapter.Fill(table);
grilla.DataSource = table;
grilla.Refresh();
grilla.Columns["sector_id"].Visible = false;
grilla.Columns["clave"].Visible = false;
grilla.Columns["sector"].HeaderText = "Sector";
grilla.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill;
SetDataBinding();
}
private void SetDataBinding()
{
this.textBoxId.DataBindings.Clear();
this.textBoxId.DataBindings.Add(new System.Windows.Forms.Binding("Text", grilla.DataSource, "sector_id"));
this.tbSector.DataBindings.Clear();
this.tbSector.DataBindings.Add(new System.Windows.Forms.Binding("Text", grilla.DataSource, "sector"));
this.tbClave1.DataBindings.Clear();
this.tbClave1.DataBindings.Add(new System.Windows.Forms.Binding("Text", grilla.DataSource, "clave"));
this.tbClave2.DataBindings.Clear();
this.tbClave2.DataBindings.Add(new System.Windows.Forms.Binding("Text", grilla.DataSource, "clave"));
}
In the code of my "Add" button, i clear the text of my controls (the controls that are binded to the datagrid), so the user insert the new values.
private void btn_agregar_Click(object sender, EventArgs e)
{
grilla.ClearSelection();
accion = DataRowAction.Add;
SetEstado();
}
private void SetEstado()
{
if (accion == DataRowAction.Add)
btn_guardar.Text = "Agregar";
if (accion == DataRowAction.Change)
btn_guardar.Text = "Modificar";
if (accion == DataRowAction.Delete)
btn_guardar.Text = "Eliminar";
if (accion == DataRowAction.Nothing)
btn_guardar.Text = "Guardar";
groupBoxControles.Enabled = accion == DataRowAction.Add || accion == DataRowAction.Change;
PanelDerechaBotones.Enabled = accion != DataRowAction.Nothing;
panelAbajo.Enabled = accion == DataRowAction.Nothing;
grilla.Enabled = accion == DataRowAction.Nothing;
if (accion == DataRowAction.Add)
{
textBoxId.Text = "0";
tbSector.Text = "";
tbClave1.Text = "";
tbClave2.Text = "";
}
if (accion == DataRowAction.Add || accion == DataRowAction.Change)
{
tbSector.Focus();
}
}
the problem is that when the user cancels this action, the row that was selected in the grid now looks all empty. (moved empty values ​​from the controls to the grid)
I know I'm missing something, but don't know what.
appreciate if someone help me.
Cancel button code
private void btn_cancelar_Click(object sender, EventArgs e)
{
accion = DataRowAction.Nothing;
SetEstado();
//((DataTable)grilla.DataSource).RejectChanges();
}
I am assuming that the cancel button is posting back and you are not rebinding? The grid has to be rebound after every postback.

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