从另一个选择中更新下拉列表

Question

I am needing to update the value of one drop down list based off the selection from a different drop down list. The caveat that I have is instead of the drop down list containing the actual value displayed on the page, it is holding the id assigned, which skews my whole logic behind it! I am wanting to update ddlLocation based off the value selected for ddlCompName on the page itself ddlCompName holds a text value like On1, On2, On3, On4 but behind the scenes it is actually housing the value of CompID

This is how ddlCompName gets populated

private void GetComputerName()
{
  this.ddlCompName.DataSource = GetComputerNames(DBToQuery);
  this.ddlCompName.DataTextField = ComputerName;
  this.ddlCompName.DataValueField = CompID;
  this.ddlCompName.DataBind();
}

And this is the update I want to run, but doesn't work due to the numeric value

protected void ddlCompName_SelectedIndexChanged(object sender, EventArgs e)
{
  if (VBS.Left(ddlCompName.SelectedValue.ToString(), 2) == "On")
  {
    ddlLocation.SelectedValue = "Building One";
  }
}

What do I need to alter so that I can make the update as desired?

EDIT -- @Nelak altering to SelectedText instead of SelectedValue throws this compile error

'System.Web.UI.WebControls.DropDownList' does not contain a definition for 'SelectedText' and no extension method 'SelectedText' accepting a first argument of type 'System.Web.UI.WebControls.DropDownList' could be found (are you missing a using directive or an assembly reference?)

Answer 1

If you want the display text rather than the value then try this

protected void ddlCompName_SelectedIndexChanged(object sender, EventArgs e)
{
  if (VBS.Left(ddlCompName.SelectedItem.Text, 2) == "On")
  {
    ddlLocation.SelectedValue = "Building One";
  }
}