4 variations shown below.
public partial class _Default : System.Web.UI.Page
{
private bool MyPageIsValid { get; set; }
protected void Page_Load(object sender, EventArgs e)
{
if (Page.IsPostBack)
{
bool valid = false; /* some routine here */
MyPageIsValid = valid;
}
}
protected void Button1_Click(object sender, EventArgs e)
{
if (this.MyPageIsValid)
{
this.TextBox1.Text = DateTime.Now.ToLongTimeString();
}
}
protected void Button2_Click(object sender, EventArgs e)
{
if (!this.MyPageIsValid) {return;}
this.TextBox1.Text = DateTime.Now.ToLongTimeString();
}
protected void Button3_Click(object sender, EventArgs e)
{
if (this.Page.IsValid)
{
this.TextBox1.Text = DateTime.Now.ToLongTimeString();
}
}
protected void Button4_Click(object sender, EventArgs e)
{
if (!this.Page.IsValid) {return;}
this.TextBox1.Text = DateTime.Now.ToLongTimeString();
}
}