一个页面上有多个用户控件实例，但仅引用了最后一个控件

问题描述

|| 我有一个“ 0”，允许用户上传文件，并以“ 1”显示它们。在父页面上，我有一个jQuery标签控件，向其中动态添加了

UserControl

的2个实例（在不同的标签上）。第二个实例工作正常，所以我知道控件可以工作。但是，当我尝试使用第一个实例上传文件时，正在引用第二个实例...因此所有属性值，控件名称等都指向第二个实例。 这就是我在隐藏代码的父页面中加载控件的方式：

protected void Page_Load(object sender,EventArgs e)
{
  MyControl ucAttachments1 = (MyControl) Page.LoadControl(\"~/controls/mycontrol.ascx\");
  ucAttachments1.ID = \"ucAttachments1\";
  ucAttachments1.Directory = \"/uploads/documents\";
  ucAttachments1.DataChanged += new MyControl.DataChangedEventHandler(DoSomething);
  phAttachments1.Controls.Add(ucAttachments1);

  MyControl ucAttachments2 = (MyControl)Page.LoadControl(\"~/controls/mycontrol.ascx\");
  ucAttachments2.ID = \"ucAttachments2\";
  ucAttachments2.Directory = \"/uploads/drawings\";
  ucAttachments2.DataChanged += new MyControl.DataChangedEventHandler(DoSomething);
  phAttachmetns2.Controls.Add(ucAttachments2);
}

在html中：

<div id=\"tabContainer\">
    <div id=\"files\">
        <asp:PlaceHolder id=\"phAttachments1\" runat=\"server\" />
    </div>
    <div id=\"drawings\">
        <asp:PlaceHolder id=\"phAttachments2\" runat=\"server\" />
    </div>
</div>

用户控制代码段：

private string directory;

override protected void OnLoad(EventArgs e)
{
    PopulateAttachmentGridview();
}

protected btnUpload_Click(object sender,EventArgs e)
{
    UploadFile(directory);
}

public string Directory
{
    get { return directory; }
    set { directory = value; }
}

如何确保正确引用我的用户控件？     

解决方法

        检查呈现给客户端的实际html和javascript，以确保没有与重复出现的控件相关的重复ID。     ,        我认为这是问题所在

MyControl ucAttachments1 = (MyControl) Page.LoadControl(\"~/controls/mycontrol.ascx\");

MyControl ucAttachments2 = (MyControl)Page.LoadControl(\"~/controls/mycontrol.ascx\");

您将控件的同一实例引用到两个不同的变量。因此，现在您具有相同实例的两个不同引用，因为现在您最后设置了\“ ucAttachments2 \”的属性，所以发生的事情是您的实例上设置了第二个控件属性。因此，无论何时尝试访问该实例实例（通过使用\“ ucAttachments1 \”或\“ ucAttachments2 \”），您将获得第二个控件的属性。 尝试做：

MyControl ucAttachments1 = new MyControl();
ucAttachments1 = (MyControl) Page.LoadControl(\"~/controls/mycontrol.ascx\");
 ucAttachments1.ID = \"ucAttachments1\";
  ucAttachments1.Directory = \"/uploads/documents\";
  ucAttachments1.DataChanged += new MyControl.DataChangedEventHandler(DoSomething);
  phAttachments1.Controls.Add(ucAttachments1);


MyControl ucAttachments2 = new MyControl();
ucAttachments2 = (MyControl) Page.LoadControl(\"~/controls/mycontrol.ascx\");
ucAttachments2.ID = \"ucAttachments2\";
  ucAttachments2.Directory = \"/uploads/drawings\";
  ucAttachments2.DataChanged += new MyControl.DataChangedEventHandler(DoSomething);
  phAttachmetns2.Controls.Add(ucAttachments2);