在C＃代码后面选择索引时，不会触发DropDownList.SelectedIndexChanged

Question

我试图在C＃代码后面的DropDownList中选择索引但是不会触发SelectedIndexChanged事件。什么是正确的方法？

  DropDownListChapterTitles.SelectedIndex = 1;


  protected void DropDownListChapterTitles_SelectedIndexChanged(object sender, EventArgs e)
  { }

Answer 1

DropDownListChapterTitles.SelectedIndex = 1;
// Call it yourself
DropDownListChapterTitles_SelectedIndexChanged(this, null);

Answer 2

检查你的标记应该是这样的

<asp:DropDownList runat="server" ID="DropDownListChapterTitles" AutoPostBack="True"
     OnSelectedIndexChange="DropDownListChapterTitles_SelectedIndexChanged">

</asp:DropDownList>

我添加了OnSelectedIndexChange="DropDownListChapterTitles_SelectedIndexChanged"