为下拉选择框添加空行的两种方法

 

1、  //将空白添加到第1行

       if (ds.Tables[0].Rows.Count > 0)
             {
                this.ddlStoreType.DataSource = ds.Tables[0];
                DataTable dt = ds.Tables[0];

                DataRow dr = dt.NewRow();
                dr[0] = "";
                dt.Rows.InsertAt(dr, 0);  //将空白添加到第1行

                this.ddlXXX.DataValueField = "value";
                this.ddlXXX.DataTextField = "display";
                this.ddlXXX.DataBind();
            }

 2、      //增加一个空项
            this.ddlXXX.Items.Insert(0, new ListItem(string.Empty, string.Empty));