奇怪连判断textbox 控件都那么难

Question

<asp:TextBox ID="user_pwd" MaxLength ="12" CssClass="text" runat ="server" TextMode="Password"></asp:TextBox>
                                    <asp:Label ID="Label3" runat="server"></asp:Label></div>

Answer 1

if (string.IsNullOrEmpty(this.user_pwd.Text.Trim()))
{
}

Answer 2

if (this.user_pwd.Text.Trim()==String.Empty)
        {
            Label3.Text="fdsa";
            return;
        }