动态生成的模板列，如何提取值

lilyraint · 发表于 2013-7-17 17:25:44

动态生成模板列：
/// <summary>
/// 创建TextBox类型的Grid列
/// </summary>
public class TemplateTextBox : ITemplate
{
      public string ControlID = "", FieldName = "";
      public TemplateTextBox()
      {
      }
      public TemplateTextBox(string ControlID, string FieldName)
      {
         this.ControlID = ControlID;
         this.FieldName = FieldName;
      }
      public void InstantiateIn(System.Web.UI.Control container)
      {
         AspNet.TextBox labGender = new AspNet.TextBox();
         labGender.ID = this.ControlID;
         labGender.BorderStyle = AspNet.BorderStyle.None;
         labGender.DataBinding += new EventHandler(TemplateTextBox_DataBinding);
         container.Controls.Add(labGender);
      }
      private void TemplateTextBox_DataBinding(object sender, EventArgs e)
      {
         AspNet.TextBox labGender = (AspNet.TextBox)sender;
         IDataItemContainer dataItemContainer = (IDataItemContainer)labGender.NamingContainer;
         labGender.Text = Convert.ToString(((DataRowView)dataItemContainer.DataItem)[this.FieldName]);
      }
}
      protected void Page_Init(object sender, EventArgs e)
      {
         tf = new FineUI.TemplateField();
         tf.HeaderText = "角色名称";
         tf.Width = Unit.Pixel(150);
         tf.ItemTemplate = new FYMat.Interface.TemplateTextBox("RoleName", "RoleName");
         Grid1.Columns.Add(tf);

         Grid1.DataKeyNames = new string[] { "RoleName" };
      }
在按钮中提取ROleName列的值，语句如下：
                  AspNet.TextBox TextBoxRoleName = (AspNet.TextBox)Grid1.Rows[i].FindControl("RoleName");
                  string RoleName = TextBoxRoleName.Text;

报错信息为：未将对象引用设置到对象的实例；
调试发现：TextBoxRoleName取出为null
怎么办呢？