Develop Reference

Copy row from datatable to another where there are common column headers

I have two datatables, I am trying to copy row from one table to another, I have tried this. the thing is that my tables are not exactly the same, both tables have common headers, but to the second table have more columns, therefore I need "smart" copy, i.e to copy the row according to the column header name.
d1:
+--------+--------+--------+
| ID | aaa | bbb |
+--------+--------+--------+
| 23 | value1 | value2 | <----copy this row
d2:
+--------+--------+--------+--------+
| ID | ccc | bbb | aaa |
+--------+--------+--------+--------+
| 23 | | value2 | value1 | <----I need this result
but this code:
string rowID=23;
DataRow[] result = dt1.Select($"ID = {rowID}");
dt2.Rows.Add(result[0].ItemArray);
gives:
d2:
+--------+--------+--------+--------+
| ID | ccc | bbb | aaa |
+--------+--------+--------+--------+
| 23 | value1 | value2 | | <---- :( NOT what I need

I think this is your homework, but here you have some simple and not very smart solution:
private DataTable DTCopySample()
{
int cnt = 0;
DataTable dt1 = new DataTable();
dt1.Columns.Add("ID");
dt1.Columns.Add("aaa");
dt1.Columns.Add("bbb");
DataTable dt2 = new DataTable();
dt2.Columns.Add("ID");
dt2.Columns.Add("ccc");
dt2.Columns.Add("bbb");
dt2.Columns.Add("aaa");
dt1.Rows.Add();
dt1.Rows[0]["ID"] = "23";
dt1.Rows[0]["aaa"] = "val1";
dt1.Rows[0]["bbb"] = "val2";
dt1.Rows.Add();
dt1.Rows[1]["ID"] = "99";
dt1.Rows[1]["aaa"] = "val99";
dt1.Rows[1]["bbb"] = "val98";
string colName = string.Empty;
foreach (DataRow row in dt1.Rows)
{
dt2.Rows.Add();
foreach (DataColumn col in dt1.Columns)
{
dt2.Rows[cnt][col.ColumnName] = row[col.ColumnName].ToString();
}
cnt++;
}
return dt2;
}
There are more smart and better solutions, but this is fast-written (2 mins) and works.
Remeber, that you have not specified columns datatypes or anything else, so I assumed there are strings everywhere for creating simple sample.

WPF Datagrid C#

I know there are a bunch of questions on this in here and tons of information elsewhere. I cannot, for some reason, get this to work. Here is one of my starting points... Add entire row to DataTable at once using list
This is for a List of Lists. The very first List should be the column headers.
dat is a List<List<string>> that looks like:
{"index", "filename0", "filename1"},
{"A-100", "yes", "no"},
{"A-200", "no", "yes"}
etc...
Code:
/// Dictionary containing as Key => FileName
/// as Value => All drawing numbers found in FileName
Dictionary<string, List<string>> AllDrawingLists = new Dictionary<string, List<string>>();
private void processGrid()
{
List<string> index = new List<string>();
/// Build a comprehensive INDEX from the dictionary - A list
/// of all the drawing numbers found in all the FIlenames
foreach (KeyValuePair<string, List<string>> item in AllDrawingLists)
{
foreach (string dwg in item.Value)
{
if (index.Contains(dwg) == false)
{
index.Add(dwg); }
}
}
List<List<string>> dat = new List<List<string>>();
List<String> headers = new List<string>();
headers.Add("Index");
foreach (KeyValuePair<string, List<string>> item in AllDrawingLists)
{
headers.Add(item.Key);
}
dat.Add(headers);
foreach(string i in index)
{
List<string> row = new List<string>();
row.Add(i);
foreach(KeyValuePair<string, List<string>> item in AllDrawingLists)
{
string cell = "no";
if (item.Value.Contains(i))
{
cell = "yes";
}
row.Add(cell);
}
dat.Add(row);
}
dataGrid.Columns.Clear();
DataTable dt = new DataTable();
int ii = 0;
foreach (List<string> row in dat)
{
if (ii == 0)
{
foreach(string t in row)
{
dt.Columns.Add(t);
}
ii++;
} else
{
dt.Rows.Add(row.ToArray<string>());
}
}
dataGrid.ItemsSource = dt.AsDataView();
}
My expected result would be :
| | | |
| index | file1 | file2 |
-------------------------
| A-100 | yes | no |
-------------------------
| A-200 | no | yes |
-------------------------
| A-300 | yes | yes |
but instead I get :
| | | |
| index | file1 | file2 |
-------------------------
| A-100 | | |
-------------------------
| A-200 | | |
-------------------------
| A-300 | | |
The List of Lists is what I would expect, clearly its working for the definition of columns. I'm not sure why nothing goes into the DataGrid after the first column
Here is the output of dat. It is what I think Im looking for. All rows and column accounted for.
Index C:\py\narrver2\lists.txt C:\py\narrver2\list2.docx
A-1001 yes yes
A-1002 yes yes
A-1003 yes yes
A-1004 no yes
A-1005 no yes
A-1006 no yes
A-1007 no yes

In case you want to keep the dot in the header name, you can set the header column binding path with the name of the header surrounded by square brackets to make the special character (in this case, the dot notation) escaped.
You can do that inside an event handler that subscribes to event AutoGeneratingColumn of your DataGrid.
private void dataGrid_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e)
{
if (e.PropertyName.Contains('.') && e.Column is DataGridBoundColumn)
{
DataGridBoundColumn dataGridBoundColumn = e.Column as DataGridBoundColumn;
dataGridBoundColumn.Binding = new Binding("[" + e.PropertyName + "]");
dataGridBoundColumn.SortMemberPath = e.PropertyName;
}
}

How to remove empty values in a DataTable rows and merge

I am trying to figure out a good way to remove empty values from rows and merge row2 to row1, row4 to row2 in a datatable.
DataTable with Empty rows to merge
---------------------
| Column1 | Column2 |
----------------------
ROW1 | XYZ | |
ROW2 | | ABC |
ROW3 | MNQ | |
ROW4 | | PQR |
Final datatable with merged rows
_____________________
| Column1 | Column2 |
----------------------
ROW1 | XYZ | ABC |
ROW2 | MNQ | PQR |
Can somebody help me accomplish this in C#?

Try to create two array that will store a column1 value and column2 value.
In loop go through all datatable rows and insert all not empty rows from column1 to array1 and rows from column2 to array2. Then on the end create new datatable that will have rows taked from array1 and array2.
For example in pseudocode.
var array1;
var array2;
for(var row in datatable)
{
if(row[column1] != null or empty)array1.push(row[column1].value);
if(row[column2] != null or empty)array2.push(row[column2].value);
}
and in the end (first check what array is biger).For example i assuming that array1 is bigger;
var newDatatable;
for(int i=0; i<array1.count; i++)
{
var row = new row;
newDatatable.row[column1].addRowValue(array1[i])
if(array2.count < i){
newDatatable.row[column2].addRowValue(array2[i])
}
}

Adjust gridview rowIndex when programmatically adding new row

I've seen this article http://asp.net-informations.com/gridview/newrow.htm and this post http://forums.asp.net/p/1534978/3725419.aspx#3725419 and I've done it for have that separator row collapsible with jquery and it's working great in display mode. The problems occuring when try to do something else with gridview, because there's a weird behaviour.. I've add a simple button that have just to set a radiobutton that's in every gridview row (except in the new added GroupHeaders rows). Then if I have added two new row he is skipping setting the last two rows in the GridView..
public void AddNewRow(object sender, GridViewRowEventArgs e)
{
GridView GridView1 = (GridView)sender;
GridViewRow NewTotalRow = new GridViewRow(-1, -1, DataControlRowType.Header, DataControlRowState.Normal);
TableCell HeaderCell = new TableCell();
HeaderCell.Attributes.Add("onclick", "collapsible('" + rowgroup + "')");
NewTotalRow.Cells.Add(HeaderCell);
TableCell HeaderCellIndex = new TableCell();
int indexCorrente = e.Row.RowIndex + index;
HeaderCellIndex.Text = indexCorrente.ToString();
NewTotalRow.Cells.Add(HeaderCellIndex);
GridView1.Controls[0].Controls.Add(NewTotalRow);
}
protected void gdDettaglio_RowCreated(object sender, GridViewRowEventArgs e)
{
bool newRow = false;
if ((DataBinder.Eval(e.Row.DataItem, "Stato") != null))
{
if (statoCorrente != Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "Stato").ToString()))
newRow = true;
}
if (newRow)
{
AddNewRow(sender, e);
}
}
Printing the row index (just to check it) next to each row I'm displaying this situation (with two GroupHeader rows added):
(The index are as they are printing them in gdDettaglio_RowCreated for GroupHeadrs rows and on gdDettaglio_OnDataBound for the other rows)
-----------------------------------------
| HEADER |
|---------------------------------------|
-----------------------------------------
| Gruppo 1 | index -1 |
|---------------------------------------|
| grp1 | x | blablabla | | index 0 |
| grp1 | y | blablabla | | index 1 |
| grp1 | z | blablabla | | index 2 |
| grp1 | x | blablabla | | index 3 |
| grp1 | x | blablabla | | index 4 |
|---------------------------------------|
| Gruppo 2 | index -1 |
|---------------------------------------|
| grp2 | x | blablabla | | index 5 |
| grp2 | y | blablabla | | index 6 |
| grp2 | z | blablabla | | index 7 |
| grp2 | z | blablabla | | index 8 |
| grp2 | z | blablabla | | index 9 |
| grp2 | z | blablabla | | index 10 |
-----------------------------------------
in the button code I've just:
foreach (GridViewRow riga in gdDettaglio.Rows)
{
if (riga.RowType == DataControlRowType.DataRow)
{
RadioButtonList rad = (RadioButtonList)riga.FindControl("rad");
rad.SelectedValue = "True";
}
}
UPDATE:
Doing the same thing on jquery work, it affects all the row:
function accettaTutte() {
$("#<%=gdDettaglio.ClientID%> tr:has(td)").each(function () {
var items = $(this).find("[id$='radDaPa'] input:radio'");
for (var i = 0; i < items.length; i++) {
if (items[i].value == 'True') {
if (!(items[i].checked)) {
items[i].checked = true;
}
break;
}
}
});
return false;
}
But I still need to do a foreach on that gridview, to update db, some idea on what could try to do? On every row I've also a "single row save" ImageButton, but clicking on it on the last two rows it's not firing the RowCommand event... It's like the two added GroupHeader rows are pushing out the last two data rows, no matter about the index.. If I click the ImageButton on the row with displayed (using Text='<%#Container.DataItemIndex%>') rowIndex 2, in the rowCommand it become rowIndex 3, but it modified the right row, the one I've clicked.. If i do the same on row 7, it become 9.. But if forced it to get value on rowIndex 11, U'm getting ArgumentOutOfRangeException, because Rows.Count It's still 11..

OK, now I am adding to the list that is GridView DataSource as many empty elements as are the GroupHeaders rows, so GridView.Rows.Count is enough to get all the rows..

How to Merge DataGridView Cell in Winforms

I have some data in a grid that currently displays like this:
------------------
|Hd1| Value |
------------------
|A | A1 |
------------------
|A | A2 |
------------------
|A | A3 |
------------------
|A | A4 |
------------------
|B | B1 |
------------------
|B | B2 |
------------------
|B | B3 |
------------------
|B | B4 |
------------------
|B | B5 |
------------------
|C | C1 |
------------------
|C | C2 |
------------------
I want to make it look like this:
|Hd | Value |
------------------
|A | A1 |
----------
| | A2 |
----------
| | A3 |
----------
| | A4 |
------------------
|B | B1 |
----------
| | B2 |
----------
| | B3 |
----------
| | B4 |
----------
| | B5 |
------------------
|C | C1 |
----------
| | C2 |
------------------
Is there any way that I can merge these cells?
I have tried in many ways also google but did not find any suitable way.
If it is possible showing this data another way without using datagridview but the result is the way I have showed, that will also solve my problem.

You must first find a duplicate values
Need to two methods:
bool IsTheSameCellValue(int column, int row)
{
DataGridViewCell cell1 = dataGridView1[column, row];
DataGridViewCell cell2 = dataGridView1[column, row - 1];
if (cell1.Value == null || cell2.Value == null)
{
return false;
}
return cell1.Value.ToString() == cell2.Value.ToString();
}
in the event, cellpainting:
private void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
e.AdvancedBorderStyle.Bottom = DataGridViewAdvancedCellBorderStyle.None;
if (e.RowIndex < 1 || e.ColumnIndex < 0)
return;
if (IsTheSameCellValue(e.ColumnIndex, e.RowIndex))
{
e.AdvancedBorderStyle.Top = DataGridViewAdvancedCellBorderStyle.None;
}
else
{
e.AdvancedBorderStyle.Top = dataGridView1.AdvancedCellBorderStyle.Top;
}
}
now in cell formatting:
if (e.RowIndex == 0)
return;
if (IsTheSameCellValue(e.ColumnIndex, e.RowIndex))
{
e.Value = "";
e.FormattingApplied = true;
}
and in form_load:
dataGridView1.AutoGenerateColumns = false;

The DataGridView control has no related properties or methods to merge cells, but you can accomplish the same using custom painting. You can use DataGridView.CellPainting event or override the Paint method.
Plus you will need to override the DataGridView.CellClick, CellEnter, CellFormatting and other methods as well in order to give your DataGridView a full featured functionality. For eg on cell click, the entire merged cell (or group of cells that constitute a merged cell) will have to be custom painted.
You can find some sample code here:
http://social.msdn.microsoft.com/forums/en-US/vbinterop/thread/5b659cbd-7d29-4da4-8b38-5d427c3762e2
http://forums.codeguru.com/showthread.php?415930-DataGridView-Merging-Cells
http://www.codeproject.com/Questions/152113/How-can-i-merge-DataGridView-Rows-Cells-with-Equal

There are some good responses on asp.net but in winforms and for this example(merging same data in columns) it is not defined.
You can use color.transparent to hide the same values in datagridview.
even by this code, same rows do not deleted and can be good for matematical calculations.
even you can define which columns to merge by your desire sort.
In this way if end of "A" was "A4" and also start of "B" was "A4" those would not be merge. which is Often more desired. (If you do not want this, better use other responses)
MergeGridviewCells(DGV,new int[] {0,1});//For example if you want to merge first columns data/then 3th column and then second column you can use new int[] {0,2,1}
private void MergeGridviewCells(DataGridView DGV, int[] idx)
{
DataGridViewRow Prev = null;
foreach (DataGridViewRow item in DGV.Rows)
{
if (Prev != null)
{
string firstCellText = string.Empty;
string secondCellText = string.Empty;
foreach (int i in idx)
{
DataGridViewCell firstCell = Prev.Cells[i];
DataGridViewCell secondCell = item.Cells[i];
firstCellText = (firstCell != null && firstCell.Value != null ? firstCell.Value.ToString() : string.Empty);
secondCellText = (secondCell != null && secondCell.Value != null ? secondCell.Value.ToString() : string.Empty);
if (firstCellText == secondCellText)
{
secondCell.Style.ForeColor = Color.Transparent;
}
else
{
Prev = item;
break;
}
}
}
else
{
Prev = item;
}
}
}
Preview:

I spent a long time looking for this as my boss didn't want to buy any off-the-shelf components. This should be submitted into the .NET code: datagridvewtextboxcell-with-span-behaviour It just works and is soo simple to use. Works with VB/C# .NET 4.5 to 6. Spans rows and columns including headers.
DataGridView.Columns.Add(new DataGridViewTextBoxColumnEx());
DataGridViewTextBoxCellEx dataGridViewCell = (DataGridViewTextBoxCellEx)DataGridView[colIdx, rowIdx];
dataGridViewCell.ColSpan = 2;
dataGridViewCell.RowSpan = 6;