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C# 使用findcontrol从动态文字控件查找值时出现问题_C#_Asp.net - Fatal编程技术网

C# 使用findcontrol从动态文字控件查找值时出现问题

C# 使用findcontrol从动态文字控件查找值时出现问题,c#,asp.net,C#,Asp.net,在动态创建的文本控件中查找控件时遇到问题。我希望能够用fnameID(x)id获取标签中的值 ASPX: 源错误: { Label lbl = (Label)Page.FindControl("fnameID0"); **Response.Write(lbl.Text);** } 尝试显式设置生成的控件的ID: protected void Page_Load(object sender, EventArgs e) { for (int i = 0; i < 50; i++)

在动态创建的文本控件中查找控件时遇到问题。我希望能够用
fnameID(x)
id获取标签中的值

ASPX:

源错误:

{
Label lbl = (Label)Page.FindControl("fnameID0");
**Response.Write(lbl.Text);**
}

尝试显式设置生成的控件的ID:

protected void Page_Load(object sender, EventArgs e)
{
    for (int i = 0; i < 50; i++)
    {
        CheckBox _checkbox = new CheckBox();
        _checkbox.ID = "dynamicCheckListBox" + Convert.ToString(i);
        Panel1.Controls.Add(_checkbox);

        LiteralControl dynLabel = new LiteralControl("<Label id='fnameID" 
            + i + "' >test" + i + "</Label><br/>");
        dynLabel.ID = "fnameID" + i.ToString();

        Panel1.Controls.Add(dynLabel);
    }

}
受保护的无效页面加载(对象发送方,事件参数e)
{
对于(int i=0;i<50;i++)
{
复选框_CheckBox=新复选框();
_checkbox.ID=“dynamicCheckListBox”+转换为字符串(i);
Panel1.控件。添加(_复选框);
LiteralControl动态标签=新的LiteralControl(“测试”+i+“
”); dynLabel.ID=“fnameID”+i.ToString(); 面板1.控件。添加(动态标签); } }
您将获得null引用异常,因为找不到具有指定ID的控件,因此
FindControl
将返回
null
,并且无法获取
null
Text
属性

Object reference not set to an instance of an object.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
{
Label lbl = (Label)Page.FindControl("fnameID0");
**Response.Write(lbl.Text);**
}
protected void Page_Load(object sender, EventArgs e)
{
    for (int i = 0; i < 50; i++)
    {
        CheckBox _checkbox = new CheckBox();
        _checkbox.ID = "dynamicCheckListBox" + Convert.ToString(i);
        Panel1.Controls.Add(_checkbox);

        LiteralControl dynLabel = new LiteralControl("<Label id='fnameID" 
            + i + "' >test" + i + "</Label><br/>");
        dynLabel.ID = "fnameID" + i.ToString();

        Panel1.Controls.Add(dynLabel);
    }

}