how can we change the value of one column on change of other column in gridview.

Introduction

In this Artcile i will show you how can we change the value of one column on change of other column in gridview.

Using the code

I am using a gridview to show records. In two columns of gridview value will be show in dropdownlists. so on change of one dropdownlist value i have to change another dropdownlist's value.

I have two column One is 'project' and second is 'module'. so i want to show modules according to value of project. 

I want to perform these action in edit mode of gridview.

Step 1: in gridview add two template fields. then add dropdownlists to EditItemtemplate of Template fields. Shown as below:

Step 2: We want modules name according to project name so we will set the autopostback property true for project dropdownlist.

step 3: Now double click on project dropdownlist for generate the selectedechanged event of dropdonlist. 

protected void ddlProject_SelectedIndexChanged(object sender, EventArgs e)
    	{
        	try
        	{
	            DropDownList ddlProject = (DropDownList)sender;
		    GridViewRow row = (GridViewRow)ddlProject.NamingContainer;

	            ddlProject = (DropDownList)GridView1.Rows[row.RowIndex].FindControl("ddlProject");
                   
		    DropDownList ddlModule = new DropDownList();

                    ddlModule = (DropDownList)GridView1.Rows[row.RowIndex].FindControl("ddlModule");
                    int iProjectID = Convert.ToInt32(ddlProject.SelectedValue);
                    modulecl_ba omodule = new modulecl_ba();
                    DataTable dtmodule = new DataTable();
                    dtmodule = omodule.getModuleName(iProjectID); 

 
                    ddlModule.DataTextField = "v_module_name";
                    ddlModule.DataValueField = "in_module_id";
                    ddlModule.DataSource = dtmodule;
                    ddlModule.DataBind();
        	}
        	catch 
		{ 
			throw; 
		}
    	} 

I hope it will help you.