Gridview edit mode won't modify textbox properties

Question

My gridview is binded to an SqlDataSource and populated dynamicaly. I am facing a problem of modifying textbox properties in the edit mode.

protected void gvData_PreRender(object sender, EventArgs e)
{
    if (this.gvData.EditIndex != -1)
        for (int i = 1; i < gvData.Rows[gvData.EditIndex].Cells.Count; i++)
        {
            LinkButton lb = new LinkButton();
            TextBox tb = new TextBox();

            foreach (string pk in Settings.PK)
                if (lb.Text == pk)
                    tb.Enabled = false;
            try
            {
                lb = (LinkButton)gvData.HeaderRow.Cells[i].Controls[0];
                tb = (TextBox)
                    gvData.Rows[gvData.EditIndex].Cells[i].Controls[0];
            }
            catch { }

            if (lb.Text.Contains(Settings.AUTOEXP))
            {
                tb.TextMode = TextBoxMode.MultiLine;
                tb.Rows = 7;
            }

            tb.Text = Truncate.ToText(tb.Text);
            tb.CssClass = "input";
            tb.ID = lb.Text;
        }

    gvData.DataBind();
}

Here the application sets sertain textboxes to multiline and all of them have class "input". With gvData.DataBind(); none of the modifications are applied. If I remove DataBind, it works. But here I face another problem. I am using those values to Update the database.

protected void gvData_RowUpdating(object sender, GridViewUpdateEventArgs e)
{        
    string updateCommand = "UPDATE " + Settings.TABLE + "SET ";
    TextBox tb = new TextBox();

    for (int i = 1; i < gvData.HeaderRow.Cells.Count; i++)
    {
        LinkButton lb = new LinkButton();

        lb = (LinkButton)gvData.HeaderRow.Cells[i].Controls[0];

        try 
        {
            tb = (TextBox)gvData.Rows[e.RowIndex].Cells[i].Controls[0];

            if (tb.Text.Length > 0 && !Settings.PK.Contains(lb.Text))
                try
                {
                    Convert.ToDouble(tb.Text);
                    updateCommand += lb.Text + " = " + tb.Text + ", ";
                }
                catch { updateCommand += lb.Text + " = " + "'" + tb.Text + "', "; } 
        }
        catch { }
    }

    updateCommand = updateCommand.Remove(updateCommand.Length - 2, 2) + " WHERE";

    foreach (string pk in Settings.PK)
    {
        updateCommand += " " + pk + " = :" + pk + " AND";
        DS.UpdateParameters.Add(
            new Parameter(pk, TypeCode.String, e.Keys[pk].ToString()));
    }

    DS.UpdateCommand = updateCommand.Remove(updateCommand.Length - 4, 4);

    gvData.DataBind();
}

Here the application sets the UpdateCommand to the datasource. Values are recieved from the textboxes. If I use gvData.DataBind(); in the PreRender, I am able to get the values from textboxes but styling does not wokr. If I don't use DataBind, styling wotks but textbox values are empty.

Do you have any suggestions? Thank you beforehands!

---

protected void gvData_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        for (int i = 1; i < e.Row.Cells.Count; i++)
        {
            try
            {
                LinkButton lb = (LinkButton)gvData.HeaderRow.Cells[i].Controls[0];
                lb.ToolTip = select.ToolTip(lb.Text);

                if (lb.Text.Contains(Settings.AUTOEXP))
                {
                    e.Row.Cells[i].ToolTip =
                        Truncate.ToText(e.Row.Cells[i].Text);
                    e.Row.Cells[i].Text =
                        Truncate.ToText(e.Row.Cells[i].Text
                            .Substring(0, 40)) + "...";
                }

                e.Row.DataItem = lb.Text;
                e.Row.Cells[i].Wrap = false;
            }
            catch { }

        }

        if ((e.Row.RowState & DataControlRowState.Edit) > 0)
        {
            for (int i = 1; i < e.Row.Cells.Count; i++)
            {
                LinkButton lb = new LinkButton();
                TextBox tb = new TextBox();

                foreach (string pk in Settings.PK)
                    if (lb.Text == pk)
                        tb.Enabled = false;
                try
                {
                    lb = (LinkButton)gvData.HeaderRow.Cells[i].Controls[0];
                    tb = (TextBox)
                        e.Row.Cells[i].Controls[0];
                }
                catch { }

                if (lb.Text.Contains(Settings.AUTOEXP))
                {
                    tb.TextMode = TextBoxMode.MultiLine;
                    tb.Rows = 7;
                }

                tb.Text = Truncate.ToText(tb.Text);
                tb.CssClass = "input";
                tb.ID = lb.Text;
            }
        }
    }

    if (e.Row.RowType == DataControlRowType.Footer)
        PopulateFooter(e.Row);

}

Answer 1

I would suggest using the onrowdatabound event handler for handling altering the display of your textboxes.

Answer 2

Figured it out.

For some reason, the problem was in one line:

tb.ID = lb.Text; 

That code in RowDataBounnd was unnecessary.

The solution is:

In Page_Load add

GridView.DataBind();

RowDataBound:

if ((e.Row.RowState & DataControlRowState.Edit) > 0)
   for (int i = 1; i < e.Row.Cells.Count; i++)
       try
       {
          LinkButton lb = (LinkButton)gvData.HeaderRow.Cells[i].Controls[0];
          TextBox tb = (TextBox)e.Row.Cells[i].Controls[0];

          if (lb.Text.Contains(Settings.AUTOEXP))
          {
              tb.TextMode = TextBoxMode.MultiLine;
              tb.Rows = 7;
          }

          tb.CssClass = "input";
       }
       catch { }

In RowUpdating the value is accessed from the TextBox.