出来个高手 Ajax控件中遍历出所有的DropDownList

Question

如题
高手出来一个帮我解决一下，如何解决用foreach 来遍历出所有的DropDownList 并且赋值，具体方法如下：
  /// <summary>
        /// 初始化一个字典类
        /// </summary>
        private Dictionary<int, string> dropItems = new Dictionary<int, string>();   #region        private void SetDictionnary()
        {
            dropItems.Add(1, "1:"+this.GetStringById("1"));
            dropItems.Add(2, "2:"+this.GetStringById("2"));
            dropItems.Add(3, "3:"+this.GetStringById("3"));
            dropItems.Add(4, "4:"+this.GetStringById("4"));
            dropItems.Add(5, "5:"+this.GetStringById("5"));
            dropItems.Add(6, "6:"+this.GetStringById("6"));
            dropItems.Add(7, "7:"+this.GetStringById("7"));
        }        #endregion 
  /// <summary>
        /// 设置DropDownList
        /// </summary>
        private void SetDropDownList()
        {
            foreach (Control ctrl in this.TabPanel1.Controls)
            {
                if(ctrl is DropDownList)
                {
                    DropDownList drop = (DropDownList) ctrl;
                    drop.DataSource = dropItems;
                    drop.DataTextField = "Value";
                    drop.DataValueField = "Key";
                    drop.DataBind();
                }
            }
        }

Answer 1

可以用ajax把需要的数据从后台读出来，在前台用js对dropdownlist进行赋值的

Answer 2

我要的是把 所有的， DropDownList 都遍历出来    foreach (Control ctrl in this.TabPanel1.Controls)
            {
                if(ctrl is DropDownList)
                {
                    DropDownList drop = (DropDownList) ctrl;
                    drop.DataSource = dropItems;
                    drop.DataTextField = "Value";
                    drop.DataValueField = "Key";
                    drop.DataBind();
                }
            }
这个是不正确的

Answer 3

foreach (Control ctrl in this.Controls) 
            { 
                if(ctrl is DropDownList) 
                { 
                    DropDownList drop =  ctrl as DropDownList; 
                   
                } 
            }