using errorprovider control if data not entered

[buddyr]

Hello,
I have form in C#.
I want to use the errorprovider control to prompt user for data if nothing is entered.
example:
I have textbox1 for user to enter name.
I have radiobuttons for job departments.

I click a button and data displays in labels.
label1.text = textbox1;
if (radiobutton1.c licked)
label3.text = radiobutton1.te xt "\r\n";

if user not enter name how can I code errorprovider to catch it and display error?
thank you

[Sl1ver]

if (textbox1.text.Trim() == string.Empty)
{      
      MessageBox.Show("Please enter a name");
} else
{
    //code to do what its suppose to do, save or whatever
}

[buddyr]

if (textbox1.text. Trim() == string.Empty)
{
ErrorProvider1. Seterror(textbo x1, "Enter your name")
else
{
label1.text = textbox1;
}
am trying this
thank you
not sure if I can do same with radiobuttons