How to hide columns in an ASP.NET GridView with auto-generated columns?

Question

GridView1.Columns.Count is always zero even SqlDataSource1.DataBind();

But Grid is ok

I can do

for (int i = 0; i < GridView1.HeaderRow.Cel         


        

Answer 1

I found Steve Hibbert's response to be very helpful. The problem the OP seemed to be describing is that of an AutoGeneratedColumns on a GridView.

In this instance you can set which columns will be "visible" and which will be hidden when you bind a data table in the code behind.

For example: A Gridview is on the page as follows.

And then in the code behind a PopulateGridView routine is called during the page load event.

protected void PopulateGridView()
{
    DataTable dt = GetDataSource();
    gv.DataSource = dt;
    foreach (DataColumn col in dt.Columns)
    {
        BoundField field = new BoundField();
        field.DataField = col.ColumnName;
        field.HeaderText = col.ColumnName;
        if (col.ColumnName.EndsWith("ID"))
        {
            field.Visible = false;
        }
        gv.Columns.Add(field);
    }
    gv.DataBind();
}

In the above the GridView AutoGenerateColumns is set to False and the codebehind is used to create the bound fields. One is obtaining the datasource as a datatable through one's own process which here I labeled GetDataSource(). Then one loops through the columns collection of the datatable. If the column name meets a given criteria, you can set the bound field visible property accordingly. Then you bind the data to the gridview. This is very similar to AutoGenerateColumns="True" but you get to have criteria for the columns. This approach is most useful when the criteria for hiding and un-hiding is based upon the column name.