Slow performance of DataGridViewRow in .NET C# Application

Question

I'm trying to figure out some behavior in an app that I'm supporting. The snippet is:

foreach (DataGridViewRow pGridRow in grdEmail.Rows)
{
    pGridRow.Cells[0].Value = chkSelectAll.Checked;
    pCount = pGridRow.Index + 1;
}

Which is essentially trying to select all rows in a grid (check a box) when a select all checkbox is clicked.

When the grid has a few rows (hundred or so) it works beautifully. However, when I have around 5000 rows in it, this thing crawls. The pGridRow.Cells[0].Value = chkSelectAll.Checked command takes a second or so (timed by putting Console.prints above and below it).

Any idea would be appreciated in resolving this.

Answer 1

What is the point of having 5000 rows visible at once?

Can't this be paginated?
Can't the checkbox be sent as checked by default?

Answer 2

Hi,

Try modifying the underlying datasource (if any) directly instead of setting the value of the cell.

//assuming datasetFoo.Tables(0) is the DataSource of the DataGridView
foreach (DataRow rowFoo in datasetFoo.Tables(0) { 
        rowFoo ("Sel") = chkSelectAll.Checked; 
    }

Answer 3

Showing thousands of rows at once is wasteful and makes it very difficult for users to find the data they need. I would definitely recommend pagination. Your users will thank you. (Unless they have specifically requested to see 5000 at once, which seems silly.)