HOW TO ADD DATABASE VALUES TO TEXTBOX IN C# VB.NET

HOW TO ADD DATABASE VALUES TO TEXTBOX IN C# VB.NET
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string cal = "select Name,Age,Dr_name from Patient_record where Refno='" + txtrefno.Text + "' ";
DataTable dt = new DataTable();
dt = obj.call(cal);
if (dt.Rows.Count > 0)
{
txtname.Text = dt.Rows[0]["Name"].ToString();
txtage.Text = dt.Rows[0]["Age"].ToString();
txtdrname.Text = dt.Rows[0]["Dr_name"].ToString();

}
else
{
MessageBox.Show("No details");
txtrefno.Focus();
}
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