how to hide a text entry in the print preview c#

Question

There is no error showing. My selection is not working, I need to hide a specific field. If the field is empty the title of that field should be hidden. I am using a printpreviewdialog to preview the details. my code:

 private void DVPrintDocument_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
    {

        //e.Graphics.DrawString("NAME          : " + dgvItem.CurrentRow.Cells[4].Value, new Font("Arial", 12, FontStyle.Regular), Brushes.Black, new Point(25, 400));
        e.Graphics.DrawString("WEIGHT      : " + txtGemWeight.Text + " Cts", new Font("Arial", 12, FontStyle.Regular), Brushes.Black, new Point(25, 440));

        //string txtSpecification = false;

        if (txtSpecification.Text == null)
        {
            txtSpecification.Visible= false;
        }
        else
        {
            e.Graphics.DrawString("SPECIFICATION   : " + txtSpecification.Text, new Font("Arial", 12, FontStyle.Regular), Brushes.Black, new Point(25, 480));
        }
    }
}

Answer 1

if(txtSpecification.Text == null) 

change it to

if(txtSpecification.Text == "")

because text by default value is not null.