private void txtPrjFilePath_Validating(object sender, CancelEventArgs e)
{
//if our radio button is selected.
//if the file doesn't have a valid projection
bool listSelected = radioSRIDFile.Checked;
bool validProjectionFile = false; //TODO
string errorMessage = string.Empty;
if (listSelected && !validProjectionFile)
{
errorMessage = "Invalid Projection File";
}
this.errorProvider1.SetError(txtPrjFilePath, errorMessage);
}