我创建了一个 Web 部件,有五种配置:在 usercontrol.ascx 中,我通过以下代码获取值:
namespace tasks_email.tasks_email_webpart
{
public partial class tasks_email_webpartUserControl : UserControl
{
public tasks_email_webpart WebPart { get; set; }
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btn_send_id_Click(object sender, EventArgs e)
{
string subject = " ";
subject = this.WebPart.SUBJECT as string;
string emailAddrS = " ";
emailAddrS = this.WebPart.EMAILADDR as string;
string checkout_changes = " ";
checkout_changes = this.WebPart.CHECKOUTLISTSNAMES as string;
SendCheckout("bo.wang@us.bnpparibas.com", subject, "this is a project test");
但是当我点击按钮时,它说:空引用异常,无论我编辑配置什么东西,变量都无法获取 SUBJECT 值
任何机构都可以告诉我如何处理吗?
*我检查了 webpart.cs,我确实写过:
namespace tasks_email.tasks_email_webpart
{
[ToolboxItemAttribute(false)]
public class tasks_email_webpart : Microsoft.SharePoint.WebPartPages.WebPart
{
[WebBrowsable(true), Category("Configurations"), Personalizable(PersonalizationScope.Shared), WebDisplayName("Subject")]
public string SUBJECT { get; set; }
在 ascx 中,我使用以下方法创建了一个按钮:
<asp:Button ID="btn_send_id" runat="server" Text=" Email_changes "
onclick="btn_send_id_Click" CssClass="Search_Submit" onclientclick="return checkna()"
/>
错误报告:
[NullReferenceException: Object reference not set to an instance of an object.]
tasks_email.tasks_email_webpart.tasks_email_webpartUserControl.btn_send_id_Click(Object sender, EventArgs e) +375
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +114
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +139
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +28
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2980