<ext:Window ID="window1" runat="server" Width="350" AutoHeight="true" Title="新增" Hidden="true" Icon="Textfield" Padding="10" LabelWidth="100">
          <Items>
            <ext:TextField ID="txtName" runat="server" InputType="Text" FieldLabel="用户名" AnchorHorizontal="90%"></ext:TextField>
          </Items>
          <Buttons>
            <ext:Button ID="Button1" Text="保存" Icon="TableSave" Width="70" runat="server">
                <DirectEvents>
                    <Click OnEvent="Button_Click"><EventMask ShowMask="true" Msg="正在保存......" /></Click>
                </DirectEvents>
            </ext:Button>
        </Buttons>     
</ext:Window> 

 protected void Button_Click(object sender, DirectEventArgs e)
        {
            if (string.IsNullOrEmpty(this.txtName.Text))
            {
                X.Msg.Alert("提示", "用户名不能为空").Show();
            }
            else
            {
                X.Msg.Alert("提示", "保存成功!").Show();
            }
        }