C# getting selected value from dropdownlist in gridview asp net

Question

How can I change the value of a textbox whenever a dropdownlist within a gridview has its value changed?

On page load, the textbox shows the selected value, but when

Answer 1

You need to use SelectedIndexChanged handler to show selected value:

Markup:

Code-behind:

protected void duty_SelectedIndexChanged(object sender, EventArgs e)
{
    GridViewRow gvr = (GridViewRow)(((Control)sender).NamingContainer);   
    DropDownList duty= (DropDownList) gvr.FindControl("duty");
    TextBox1.Text = duty.SelectedItem.Value;
}