validating textbox in windows form applications

Question

My scenario is:

Not allowing spaces at starting position of textbox after enter one or more characters text box allows spaces

Below not applicable to my sce

Answer 1

I believe that lazyDBA's answer is correct for your requirements, so with the message box something like:

if (textBox1.Text.Length == 0)
{
   if (e.Handler = (e.KeyChar == (char)Keys.Space))
   {
       MessageBox.Show("space not allowed!");
   }  
}`