indradeo says:
protected void calculate_Click(object sender, EventArgs e)
{
String Label = "Label20.Text";
if (Label == "No_Error")
{
Button1.Visible = true;
}
calcualtion();
calcualtion1();
calcualtion2();
calcualtion3();
}
Replace above code with below code.
protected void calculate_Click(object sender, EventArgs e)
{
string Label = Label20.Text;
if (Label == "No_Error")
{
Button1.Visible = true;
}
calcualtion();
calcualtion1();
calcualtion2();
calcualtion3();
//error();
}