I create method that when a user selects a db table from the combobox, a number of new comboboxes will be generated with each of them shows the table column name. The problem is when I select the second or third db table, the column names associated with those tables are not showed. Instead, the columns of the first table remain exist. Could someone suggest how to remove the comboboxes from the previous selection and show the new ones?
private void cboTable_SelectedIndexChanged(object sender, EventArgs e)
{
string tableName = cboTable.SelectedItem.ToString();
List<string> columnList = GetDatabaseList(tableName);
int i = 0;
foreach (var column in columnList)
{
ComboBox cb = new ComboBox();
cb.Location = new Point(475, 25 * i + 235);
this.Controls.Add(cb);
cb.Items.Add(column);
cb.SelectedIndex = -1;
cb.Refresh();
cb.SelectedIndex = 0;
i++;
}
}
I have a datagridview with values that I add manualy with a datasource, however I want to add a button where the user can shuffle the order of where the values are located in the datagridview. Does anyone have an idead on how to apply this?
if it comes from sql statement with
SELECT * FROM table
ORDER BY NEWID()
but if it is a different form of datasource
var data = //un randomed data
var randomData = data.OrderBy(x => Guid.NewGuid()).ToList();
//then bind randomData to your datasource
so on button click, update it by
getData(){
//use either sql statement or OrderBy() then bind
}
Add a hidden column that contains a random number and sort the rows using that.
If you set AutoGenerateColumns to false you can specify the order of the columns.
void ShuffleDataGridView(DataGridView dataGridView, DataTable dataTable)
{
// add or update random sort order column
const string randomSortConst = "RandomSort";
if (!dataTable.Columns.Contains(randomSortConst))
{
dataTable.Columns.Add(randomSortConst, typeof(int));
}
var rand = new Random();
foreach (DataRow drw in dataTable.Rows)
{
drw[randomSortConst] = rand.Next();
}
// randomize column display
dataGridView.AutoGenerateColumns = false;
dataGridView.AllowUserToOrderColumns = false;
dataGridView.Columns.Clear();
var columnsToAdd = new List<DataColumn>();
foreach (DataColumn dcl in dataTable.Columns)
{
if (!(dcl.ColumnName == randomSortConst))
{
columnsToAdd.Add(dcl);
}
}
while (columnsToAdd.Count > 0)
{
var j = rand.Next(0, columnsToAdd.Count - 1);
var dgvtbc = new DataGridViewTextBoxColumn
{
DataPropertyName = columnsToAdd[j].ColumnName,
HeaderText = columnsToAdd[j].ColumnName // remove this line to hide column headings
};
dataGridView.Columns.Add(dgvtbc);
columnsToAdd.RemoveAt(j);
}
// sort the rows using the hidden random column
dataGridView.DataSource = new DataView(dataTable, string.Empty, randomSortConst, DataViewRowState.CurrentRows);
}
I have a DataGridView in a C# WinForms project in which, when the user clicks on certain DGV cells, the cell changes to a DataGridViewComboBoxCell and the ComboBox is populated with some values for the user to select. Here's the form code for the DataGridView_Click event:
private void dgvCategories_Click(Object sender, DataGridViewCellEventArgs e)
{
if (e.ColumnIndex == 5 && !(dgvCategories.Rows[e.RowIndex].Cells[e.ColumnIndex].GetType().Name == "DataGridViewComboBoxCell"))
{
// Bind combobox to dgv and than bind new values datasource to combobox
DataGridViewComboBoxCell cboNewValueList = new DataGridViewComboBoxCell();
// Get fields to build New Value query
List<string> lsNewValuesResult = new List<string>();
string strCategory = dtCategories.Rows[e.RowIndex][1].ToString();
string strCompanyName = cboSelectCompany.Text;
string strQueryGetNewValuesValidationInfo = "SELECT validationdb, validationtable, validationfield, validationfield2, validationvalue2" +
" FROM masterfiles.categories" +
" WHERE category = #category";
//" WHERE category = '" + strCategory + "'";
// Pass validation info query to db and return list of New Values
db getListOfNewValues = new db();
lsNewValuesResult = getListOfNewValues.GetNewValuesList(strQueryGetNewValuesValidationInfo, strCategory, strCompanyName);
//Populate the combobox with the list of New Values
foreach (string strListItem in lsNewValuesResult)
{
cboNewValueList.Items.Add(strListItem);
}
//
dgvCategories[e.ColumnIndex, e.RowIndex] = cboNewValueList;
}
}
Here's the code in the db class that populates the ComboBox (this likely isn't necessary to include for the purposes of this question, but for the sake of completeness, I'm including it, in case is it relevant):
public List<string> GetNewValuesList(string strValidationInfoQuery, string strCategory, string strCompanyName)
{
List<string> lsValidationInfo = new List<string>();
List<string> lsNewValuesList = new List<string>();
using (NpgsqlConnection conn = new NpgsqlConnection(connString))
using (NpgsqlCommand cmd = new NpgsqlCommand(strValidationInfoQuery, conn))
{
cmd.Parameters.AddWithValue("category", strCategory);
conn.Open();
using (NpgsqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
int intReaderIndex;
for (intReaderIndex = 0; intReaderIndex <= reader.FieldCount - 1; intReaderIndex++)
{
// reader indexes 3 & 4 correspond to categories.validationfield2 and validationvalue2, which can be null
if (string.IsNullOrEmpty(reader[intReaderIndex].ToString()))
{
lsValidationInfo.Add("");
}
else
{
lsValidationInfo.Add(reader.GetString(intReaderIndex));
}
//Console.WriteLine("reader index " + intReaderIndex + ": " + reader.GetString(intReaderIndex));
}
}
}
}
string strValidationDb = lsValidationInfo[0];
string strValidationTable = lsValidationInfo[1];
string strValidationField = lsValidationInfo[2];
string strValidationField2 = lsValidationInfo[3];
string strValidationValue2 = lsValidationInfo[4];
string strQueryGetNewValues = "SELECT DISTINCT " + strValidationField +
" FROM " + strValidationDb + "." + strValidationTable +
" WHERE company_id = (SELECT id FROM company WHERE name = '" + strCompanyName + "')";
if (!string.IsNullOrEmpty(strValidationField2) && !string.IsNullOrEmpty(strValidationValue2)) strQueryGetNewValues += " AND " + strValidationField2 + " = '" + strValidationValue2 + "'";
strQueryGetNewValues += " ORDER BY " + strValidationField;
using (NpgsqlConnection conn = new NpgsqlConnection(connString))
using (NpgsqlCommand cmd = new NpgsqlCommand(strQueryGetNewValues, conn))
{
conn.Open();
using (NpgsqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
int intReaderIndex;
for (intReaderIndex = 0; intReaderIndex <= reader.FieldCount - 1; intReaderIndex++)
{
// reader indexes 3 & 4 correspond to categories.validationfield2 and validationvalue2, which can be null
if (string.IsNullOrEmpty(reader[intReaderIndex].ToString()))
{
lsNewValuesList.Add("");
}
else
{
lsNewValuesList.Add(reader.GetString(intReaderIndex));
}
Console.WriteLine("reader index " + intReaderIndex + ": " + reader.GetString(intReaderIndex));
}
}
}
}
return lsNewValuesList;
}
The combobox is getting populated, as I can access the items in lsNewValuesResult in the _Click method. The DGV Edit Mode is set to EditOnEnter. I tried EditOnKeystroke, but that didn't cause the combobox to expand on mouse click.
This is what the combobox looks like when the cell is clicked on and the CBO is populated and added to the DGV cell:
That's after I clicked each of the two cells.
[RESOLVED]
See my Answer below.
Unfortunately solving this revealed a new issue.
I'm about to publicly admit that I'm stupid:
For design and functionality reasons that are required for this project, I am manually setting the widths and names of the DGV's columns, and I also need the 2nd through 4th columns ReadOnly = true. Well, I inadvertently set the 5th column - the column that this question is about to ReadOnly = true as well.
Thank you all for your attempts at answering. This just serves to remind us how something so simple can cause a seemingly big issue and is so easy to overlook!
If I recognize your problem correctly, in my test app i add a DataGridView whit 6 column, EditMode = EditOnEnter
(Others need three time click to open dropdown, As far as I tried) and handle CellStateChanged envent.
private void dgvCategories_CellStateChanged(object sender, DataGridViewCellStateChangedEventArgs e)
{
if (e.StateChanged == DataGridViewElementStates.Selected)
{
DataGridViewCell cell = e.Cell;
int columnIndex = cell.ColumnIndex;
int rowIndex = cell.RowIndex;
//---IF CONDITIONS--
//columnIndex == 5
// Only cells in Columns[5]
//cell.Selected
// Because this event raised two time, first for last selected cell and once again
// for currently selected cell and we need only currently selected cell.
//cell.EditType.Name != "DataGridViewComboBoxEditingControl"
// If this cell "CellStateChanged" raised for second time, only other cell types allowed
// to edit, otherwise the current cell lost last selected item.
if (columnIndex == 5 && cell.Selected && cell.EditType.Name != "DataGridViewComboBoxEditingControl")
{
DataGridViewComboBoxCell cboNewValueList = new DataGridViewComboBoxCell();
//Add items to DataGridViewComboBoxCell for test, replace it with yours.
for (int i = 0; i < 10; i++)
cboNewValueList.Items.Add($"Item {i}");
dgvCategories[columnIndex, rowIndex] = cboNewValueList;
}
}
}
NOTE: user must click two time in a cell to open drop down menu.
Edit One: As Reza Aghaei suggest for single click in cell:
private void dgvCategories_CellClick(object sender, DataGridViewCellEventArgs e)
{
DataGridViewComboBoxEditingControl editingControl = dgvCategories.EditingControl as DataGridViewComboBoxEditingControl;
if (editingControl != null)
editingControl.DroppedDown = true;
}
You might need to turn AutoGenerateColumns off:
Also, it seems to take a three clicks for the dropdown to pop.
public Form1()
{
InitializeComponent();
dataGridView1.AutoGenerateColumns = false;
dataGridView1.DataSource = GetDataSource();
DataGridViewComboBoxColumn dgvcbc = new DataGridViewComboBoxColumn();
dgvcbc.Items.Add("R0C0");
dgvcbc.Items.Add("R1C0");
dgvcbc.Items.Add("R2C0");
dgvcbc.Items.Add("R3C0");
dgvcbc.DataPropertyName = "Col0";
dataGridView1.Columns.Add(dgvcbc);
}
DataTable GetDataSource()
{
var dtb = new DataTable();
dtb.Columns.Add("Col0", typeof(string));
dtb.Columns.Add("Col1", typeof(string));
dtb.Columns.Add("Col2", typeof(string));
dtb.Columns.Add("Col3", typeof(string));
dtb.Columns.Add("Col4", typeof(string));
dtb.Rows.Add("R0C0", "R0C1", "R0C2", "R0C3", "R0C4");
dtb.Rows.Add("R1C0", "R1C1", "R1C2", "R1C3", "R1C4");
dtb.Rows.Add("R2C0", "R2C1", "R2C2", "R2C3", "R2C4");
dtb.Rows.Add("R3C0", "R3C1", "R3C2", "R3C3", "R3C4");
return dtb;
}
Are you maybe getting an error which is not being shown for some reason?
If I use your code, DataGridViewComboBoxCell seems to be populated with values, but I get DataGridViewComboBoxCell value is not valid runtime error.
This test code is working fine for me:
private void dgvCategories_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
DataGridViewComboBoxCell cboNewValueList = new DataGridViewComboBoxCell();
List<string> lsNewValuesResult = new List<string>();
lsNewValuesResult.Add("Value1");
lsNewValuesResult.Add("Value2");
lsNewValuesResult.Add("Value3");
foreach (string strListItem in lsNewValuesResult)
{
cboNewValueList.Items.Add(strListItem);
}
dgvCategories[e.ColumnIndex, e.RowIndex] = cboNewValueList;
// Added setting of initial value
cboNewValueList.Value = cboNewValueList.Items[0];
}
So maybe try setting the initial value for your DataGridViewComboBoxCell after you add it to the DataGridView.
You can consider the following facts about DataGridView:
If you set AutoGenerateColumns to false, then you need to add columns to Columns collection manually.
If you set AutoGenerateColumns to true, when you assign the data to DataSource, the control generates columns automatically for the data source. In this case, the control looks in list of columns of the data source and for each column if there's no column in the Columns collection of the control having the same DataPropertyName as data source's column name, it will add a column to Columns collection.
DataPropertyName of the datagridviews' columns determines the bound column of the data source.
You usually want to add DataGridViewXXXXColumn to columns collection rather than using a DataGridViewXXXXCell for a cell.
If you set EditMode to EditOnEnter, then if you click on dropdown button, one click is enough. If you click on cell content, two clicks is needed.
If you would like to make it single click even if you click on cell content, take a look at this post. (Note: I haven't used this is the example, it's a bit annoying.)
you can set DisplayStyle to Nothing, then it shows the column as a combo box, just in edit mode.
A basic example on using DataGridViewComboBoxColumn
I suppose you are going to show a list of Products having (Id, Name, Price, CategoryId) in a DataGridView and the CategoryId should come from a list of Categories having (Id, Name) and you are going to show CategoryId as a ComboBox.
In fact it's a basic and classic example of DataGridViewComboBoxColumn:
private void Form1_Load(object sender, EventArgs e) {
var categories = GetCategories();
var products = GetProducts();
var idColumn = new DataGridViewTextBoxColumn() {
Name = "Id", HeaderText = "Id", DataPropertyName = "Id"
};
var nameColumn = new DataGridViewTextBoxColumn() {
Name = "Name", HeaderText = "Name", DataPropertyName = "Name"
};
var priceColumn = new DataGridViewTextBoxColumn() {
Name = "Price", HeaderText = "Price", DataPropertyName = "Price"
};
var categoryIdColumn = new DataGridViewComboBoxColumn() {
Name = "CategoryId", HeaderText = "Category Id", DataPropertyName = "CategoryId",
DataSource = categories, DisplayMember = "Name", ValueMember = "Id",
DisplayStyle = DataGridViewComboBoxDisplayStyle.Nothing
};
dataGridView1.Columns.AddRange(idColumn, nameColumn, priceColumn, categoryIdColumn);
dataGridView1.EditMode = DataGridViewEditMode.EditOnEnter;
dataGridView1.AutoGenerateColumns = false;
dataGridView1.DataSource = products;
}
public DataTable GetProducts() {
var products = new DataTable();
products.Columns.Add("Id", typeof(int));
products.Columns.Add("Name", typeof(string));
products.Columns.Add("Price", typeof(int));
products.Columns.Add("CategoryId", typeof(int));
products.Rows.Add(1, "Product 1", 100, 1);
products.Rows.Add(2, "Product 2", 200, 2);
return products;
}
public DataTable GetCategories() {
var categories = new DataTable();
categories.Columns.Add("Id", typeof(int));
categories.Columns.Add("Name", typeof(string));
categories.Rows.Add(1, "Category 1");
categories.Rows.Add(2, "Category 2");
return categories;
}
Learn more
To learn more about DataGridView, take a look at DataGridView Control (Windows Forms). It contains links to some documentations and useful How To articles, including:
DataGridView Control Overview
Basic Column, Row, and Cell Features in the Windows Forms DataGridView Control
Basic Formatting and Styling in the Windows Forms DataGridView Control
Column Types in the Windows Forms DataGridView Control
I want to display grid with multiple columns (like in RepositoryItemGridLookUpEdit) after click on cell in column, but if user don't want to pick item from grid, he can write something else (like in RepositoryItemComboBox). How to combine this two features?
//user can write, but only one column
RepositoryItemComboBox cbeMaterialy = new RepositoryItemComboBox();
DataTable dt = Getdt();
cbeMaterialy.Items.Clear();
foreach(DataRow item in dt.Rows)
{
cbeMaterialy.Items.Add(item);
}
gvView.Columns["ColumnName"].ColumnEdit = cbeMaterialy;
//user cannot write but multiple columns
RepositoryItemGridLookUpEdit editor = new RepositoryItemGridLookUpEdit();
editor.DataSource = dt;
column.ColumnEdit = editor;
//SOLUTION!
I mixed some answer from Devexpress team and came up with this:
public class Main()
{
//user can choose element from DB or write new value
RepositoryItemGridLookUpEdit riglue = new RepositoryItemGridLookUpEdit();
MyGridLookupDataSourceHelper.SetupGridLookUpEdit(riglue, GetMaterialyDataView(), "Kod", "Kod");
elementsEditGrid.gvView.Columns[ColumnName].ColumnEdit = riglue;
}
///////////////////
public class MyGridLookupDataSourceHelper
{
RepositoryItemGridLookUpEdit edit;
public MyGridLookupDataSourceHelper(RepositoryItemGridLookUpEdit edit, ITypedList dataSource, string displayMember, string valueMember)
{
this.edit = edit;
//enable writing into RepositoryItemGridLookUpEdit
edit.TextEditStyle = DevExpress.XtraEditors.Controls.TextEditStyles.Standard;
edit.DataSource = dataSource;
edit.DisplayMember = displayMember;
edit.ValueMember = valueMember;
edit.ProcessNewValue += edit_ProcessNewValue;
AddExistingValuesToDataSource();
}
public static void SetupGridLookUpEdit(RepositoryItemGridLookUpEdit edit, ITypedList dataSource, string displayMember, string valueMember)
{
new MyGridLookupDataSourceHelper(edit, dataSource, displayMember, valueMember);
}
//Add new values to temporary data source (not to DataBase!)
void edit_ProcessNewValue(object sender, DevExpress.XtraEditors.Controls.ProcessNewValueEventArgs e)
{
GridLookUpEdit lookUp = sender as GridLookUpEdit;
RepositoryItemGridLookUpEdit ri = lookUp.Properties;
DataTable dt = (ri.DataSource as DataView).Table;
DataRow row = dt.NewRow();
row[ri.DisplayMember] = e.DisplayValue;
row[ri.ValueMember] = e.DisplayValue;
dt.Rows.Add(row);
ri.View.RefreshData();
e.Handled = true;
//if user wants to add new values to database (data source)
//INSERT INTO DataSourceTable (ColumnName) VALUES (e.DisplayValue)
}
//Adds to temporary data source values already stored in RepositoryItemGridLookUpEdit (in case values aren't from DB)
void ProcessExistingValues(RepositoryItemGridLookUpEdit sender, object value)
{
RepositoryItemGridLookUpEdit ri = sender;
DataTable dt = (ri.DataSource as DataView).Table;
DataRow row = dt.NewRow();
row[ri.DisplayMember] = value;
row[ri.ValueMember] = value;
dt.Rows.Add(row);
ri.View.RefreshData();
}
private void AddExistingValuesToDataSource()
{
//SELECT from DB values that are already in riglue and add them to TEMPORARY DATA SOURCE (in case values aren't from DB)
//DataView dataView = SELECT ColumnName FROM table WHERE rowID = XXX
foreach (DataRow row in dataView.AsEnumerable())
{
string kod = (string)row["ColumnName"];
ProcessExistingValues(this.edit, kod);
}
}
}
You can set the RepositoryItemGridLookUpEdit.TextEditStyle property to Standard and you will be able to type. When a user types something different from what is contained in the lookup data source, the RepositoryItemGridLookUpEdit.ProcessNewValue event will be raised. In the event handler, you can add a new value to the data source to use it further.
RepositoryItemComboBox doesn't has DataSourse property, which allow to bind table with multiple column.
ComboBoxEdit Has DataSourse property, So you can bnd table with multiple column, OR create multiple column.
I created custom datatype classes that format the data the way I need it. The data I retrieve from the database comes as .NET base types, so I need to loop through the DataTable, convert each item into it's custom type, and put the converted item into a new table. I also copy the column names from the old table to the new one. The problem is, when I bind a GridView to my new table, it throws an exception:
HttpException:
The data source for GridView with id 'TestGrid' did not have any properties
or attributes from which to generate columns. Ensure that your data source
has content.
Stack Trace:
at System.Web.UI.WebControls.GridView.CreateAutoGeneratedColumns(PagedDataSource dataSource)
at System.Web.UI.WebControls.GridView.CreateColumns(PagedDataSource dataSource, Boolean useDataSource)
at System.Web.UI.WebControls.GridView.CreateChildControls(IEnumerable dataSource, Boolean dataBinding)
at System.Web.UI.WebControls.CompositeDataBoundControl.PerformDataBinding(IEnumerable data)
at System.Web.UI.WebControls.GridView.PerformDataBinding(IEnumerable data)
at System.Web.UI.WebControls.DataBoundControl.OnDataSourceViewSelectCallback(IEnumerable data)
at System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback)
at System.Web.UI.WebControls.DataBoundControl.PerformSelect()
at System.Web.UI.WebControls.BaseDataBoundControl.DataBind()
at System.Web.UI.WebControls.GridView.DataBind()
What do I need to add to my DataTable to get autogeneratecolumns to work?
Edit: Here is the code for the DataTable:
// Populate first DataTable with data from database.
adapter = new DataAdapter("SELECT status, date_ordered, date_due FROM import_table", OpenConnection);
DataTable originalTable = new DataTable();
adapter.Fill(originalTable)
// Second DataTable for converted table data.
DataTable convertedTable = new DataTable();
// The list of custom datatypes to convert to.
Type[] newTypes = {typeof(TrackingStatus), typeof(Date), typeof(Date)};
// Set the ColumnName and DataType on each column of the new table.
for(int i = 0; i < originalTable.Columns.Count; i++)
{
convertedTable.Columns.Add();
convertedTable.Columns[i].ColumnName = originalTable.Columns[i].ColumnName;
if(newTypes.Length > i)
convertedTable.Columns[i].DataType = newTypes[i];
}
// Convert each item from the old table and add it to the new table.
foreach(DataRow oldRow in originalTable.Rows)
{
DataRow newRow = convertedTable.NewRow();
for(int i = 0; i < convertedTable.Columns.Count; i++)
{
if(newTypes.Length <= i)
newRow[i] = oldRow[i];
else if(newTypes[i] == typeof(Date))
newRow[i] = Date.FromObject(oldRow[i]);
else if(newTypes[i] == typeof(TrackingStatus))
newRow[i] = TrackingStatus.FromObject(oldRow[i]);
else if(newTypes[i] == typeof(EmailAddress))
newRow[i] = EmailAddress.FromObject(oldRow[i]);
}
convertedTable.Rows.Add(newRow);
}
// Bind the GridView.
displayGrid.DataSource = convertedTable;
displayGrid.DataBind();
Instead of creating a new datatable when you convert each to custom types, create a new List and bind the list to the datasource. e.g.
var list = new List<MyClass>();
var myType = //Convert your type
list.Add(myType);
grid.DataSource = list;
And ofcourse this all is just an idea of how to do it.
UPDATE:
Saw your code afterwards:
Try this:
Create a class called ImportRow
class ImportRow
{
private string m_Status = string.Empty;
private DateTime m_DateOrdered;
private DateTime m_DateDue;
public ImportRow() { }
public string Status
{
get { return m_Status; }
set { m_Status = value; }
}
public DateTime DateOrdered
{
get { return m_DateOrdered; }
set { m_DateOrdered = value; }
}
public DateTime DateDue
{
get { return m_DateDue; }
set { m_DateDue = value; }
}
}
Then use it as:
var importedData = new List<ImportRow>();
foreach (DataRow oldRow in originalTable.Rows)
{
var newRow = new ImportRow();
newRow.Status = oldRow["status"].ToString();
newRow.DateDue = Convert.ToDateTime(oldRow["date_due"].ToString());
newRow.DateOrdered = Convert.ToDateTime(oldRow["date_ordered"].ToString());
importedData.Add(newRow);
}
Then
displayGrid.DataSource = importedData;
displayGrid.DataBind();
Your custom type needs public properties like these:
public class Foo
{
public int Id;
public string Name;
}
or you need to use the DataTable itself as DataSource.