Last couple of days i’ve been trying to add a couple (750+) columns into a DataGridView. Initially i tried the following:
this.dataGridView1.ColumnCount = 750;
The code above results in the following error: Sum of the columns’ FillWeight values cannot exceed 65535. Then i tried the following:
DataGridViewColumn[] columns = new DataGridViewColumn[750];
for ( int i = 0; i < columns.Length; ++i )
{
DataGridViewColumn column = new DataGridViewColumn();
column.CellTemplate = new DataGridViewTextBoxCell();
column.FillWeight = 1;
columns[i] = column;
}
this.dataGridView1.Columns.AddRange( columns );
This results in the following error: At least one of the DataGridView control’s columns has no cell template. Thus i tried the following:
DataGridViewColumn[] columns = new DataGridViewColumn[750];
for ( int i = 0; i < columns.Length; ++i )
{
DataGridViewColumn column = new DataGridViewTextBoxColumn();
column.FillWeight = 1;
columns[i] = column;
}
this.dataGridView1.Columns.AddRange( columns );
This code works but the AddRange call took about 15 seconds to complete. With the aid of a collegue and Reflector i set the ColumnHeadersHeightSize to DisableResizing. This reduced the calltime to less than 0.5 seconds 
Thank you so much! I had the very same problem…
Hi TimVan
I want create new property ( Rows , Cols) to DataGridView
(->So I can choice and set Rows munber and cols munber from form design)
I have create a new UserControl
———-
Public Property Cols() As Integer
Get
Return Me._Cols
End Get
Set(ByVal value As Integer)
Me._Cols = value
Me.Invalidate()
End Set
End Property
——————
on form design display property Cols, I don’t know after that what I must todo
Please help me !
@Le Hai
I’m not sure what you’re trying to achieve. A DataGridView already has properties ColumnCount and RowCount.
The performance improvement is un-believable when you disable columnheaderresizing! BRILLIANT
For those interested in the VB.NET translation, (and I hope the author does notmind) here it is
Dim columns As DataGridViewColumn() = New DataGridViewColumn(749) {}
For i As Integer = 0 To columns.Length - 1
Dim column As DataGridViewColumn = New DataGridViewTextBoxColumn()
column.FillWeight = 1
columns(i) = column
Next
Me.dataGridView1.Columns.AddRange(columns)
Thanks!!! Finally my performance issue with DataGridView has been solved.