急问:我想封装一个DropDownList控件,创建一个子控件,加一个验证属性
如题,报错:不允许使用子控件主要代码如下:
private RequiredFieldValidator fieldValiator;
/// <summary>
/// 创建子控件
/// </summary>
protected override void CreateChildControls()
{
base.CreateChildControls();
validator = new RequiredFieldValidator();
validator.ID = this.ID + "_Val";
.....
Controls.Add(validator );
} --------------------编程问答-------------------- 自己顶 --------------------编程问答-------------------- 能把问题再说仔细点吗? --------------------编程问答-------------------- 我想做一个自定义控件,在 DropDownList控件里增加一个是否允许为空的属性 --------------------编程问答-------------------- 顶起来 --------------------编程问答-------------------- 重写父类方法:CreateControlCollection()
protected override System.Web.UI.ControlCollection CreateControlCollection()
{
return new ControlCollection(this);
}
=======================================================================
Quiet easy, huh!? If you have the same problem when inheriting from out-of-the-box control, this will be the fix.
Hope this helps.
Reference: http://www.codeproject.com/KB/aspnet/DoesNotAllowChildControls.aspx
顺便说一句,遇到解决不了的问题,请参考Google,语言选择英文。
http://www.google.com.hk/search?hl=en&source=hp&q=Does+Not+Allow+Child+Controls&meta=&aq=f&aqi=g-m2&aql=&oq=&gs_rfai=
补充:.NET技术 , ASP.NET