在GridView中用DataTable，定义模板页，PostBack后TextBox值犹在，但dropDownList值没了，请高手解决......

首先模板类如下
======
    public class MyTemplate : ITemplate
    {
        private SWT.Components.DataTableColumnInfo _DTColumnInfo;
        private ListItemCollection _ListItems;

        public MyTemplate(SWT.Components.DataTableColumnInfo toColumnInfo,ListItemCollection taItems)
        {
            this._DTColumnInfo = toColumnInfo;
            this._ListItems = taItems;
        }

        public void InstantiateIn(Control toContainer)
        {
            if (this._DTColumnInfo.ControlTypeName == "TextBox") {
                string lcID = toContainer.ID;
                lcID = toContainer.ClientID;
                TextBox loEdtBox = new TextBox();
                loEdtBox.ID = "edt" + this._DTColumnInfo.Name;
                loEdtBox.EnableViewState = true;
                loEdtBox.DataBinding += new EventHandler(this.OnDataBinding);
                loEdtBox.Width = this._DTColumnInfo.Width;
                toContainer.Controls.Add(loEdtBox);
                if (this._DTColumnInfo.Type == "System.Int32") {
                    CompareValidator loCompareInteger = new CompareValidator();
                    loCompareInteger.ControlToValidate = loEdtBox.ID;
                    loCompareInteger.Operator = ValidationCompareOperator.DataTypeCheck;
                    loCompareInteger.Type = ValidationDataType.Integer;
                    loCompareInteger.ErrorMessage = "！";
                    toContainer.Controls.Add(loCompareInteger);
                }
            }
            else if (this._DTColumnInfo.ControlTypeName == "DropDownList")
            {
                DropDownList loDDL = new DropDownList();
                loDDL.ID = "ddl" + this._DTColumnInfo.Name;
                loDDL.CssClass = "dropdown_default";
                loDDL.EnableViewState = true;
                foreach (ListItem loItem in this._ListItems) {
                    loDDL.Items.Add(loItem);
                }

                loDDL.DataBinding += new EventHandler(this.OnDataBinding);
                toContainer.Controls.Add(loDDL);
            }
            else if (this._DTColumnInfo.ControlTypeName == "CheckBox")
            {
                CheckBox loChkBox = new CheckBox();
                loChkBox.ID = "chk" + this._DTColumnInfo.Name;
                loChkBox.EnableViewState = true;
                loChkBox.DataBinding += new EventHandler(this.OnDataBinding);
                toContainer.Controls.Add(loChkBox);
            }
        }

        public void OnDataBinding(object sender, EventArgs e)
        {
            GridViewRow loContainer = (GridViewRow)((Control)sender).NamingContainer;
            if (this._DTColumnInfo.ControlTypeName == "TextBox")
            {
                TextBox loEdtBox = (TextBox)sender;
                loEdtBox.Text = ((DataRowView)loContainer.DataItem)[_DTColumnInfo.Name].ToString();
            }
            else if (this._DTColumnInfo.ControlTypeName == "DropDownList")
            {
                DropDownList loDDL = (DropDownList)sender;
                ListItem loSelItem = loDDL.Items.FindByValue((((DataRowView)loContainer.DataItem)[_DTColumnInfo.Name].ToString()));
                if (loSelItem != null)
                {
                    loSelItem.Selected = true;
                }
            }
            else if (this._DTColumnInfo.ControlTypeName == "CheckBox")
            {
                CheckBox loChkBox = (CheckBox)sender;
                loChkBox.Checked = Convert.ToBoolean(((DataRowView)loContainer.DataItem)[_DTColumnInfo.Name].ToString());
            }
        }
    }

==========
Page_Load如下：
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack) {

                fillGridView("add");//根据动态构造的DataTable（并非来自数据库），构建GridView列
                addInitial();//对部分控件赋初始值
                this.grdChapter.EnableViewState = true;//grdChapter为GridView控件
           }
===========
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
问题一：
如果将动态构建GridView列的“fillGridView（）”放在“IsPostBack”里面，单击Button后，GridView中我自己定义的TextBox和DropDownList就没有了。为什么？
问题二：
为什么GridView.DataSource  == null？
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

问题三：
我将“fillGridView（）”拿到了“IsPostBack”外面，
页面上有一个Button，单击事件中读取Gridview中各单元值，GridView中每一行有edtQuestionNum（TextBox控件）和ddlQuestionType（DropDownList控件）示例代码如下，
            foreach (GridViewRow loCurRow in this.grdChapter.Rows) {
                if (loCurRow.RowType == DataControlRowType.DataRow) {
                        if (loCurRow.FindControl("edtQuestionNum") != null)
                        {
                            Response.Write(((TextBox)loCurRow.FindControl("edtQuestionNum")).Text + "||");
                        }
                        if (loCurRow.FindControl("ddlQuestionType") != null)
                        {
                            Response.Write(((DropDownList)loCurRow.FindControl("ddlQuestionType")).SelectValue+ ">>");
                        }
                }
            }

为什么每次打印在Page上的TextBox是我填写的值，而DropDownList都是第一条的Value？

7 个解决方案

#1

太长了，看的头晕

#2

to:
问题一：
如果将动态构建GridView列的“fillGridView（）”放在“IsPostBack”里面，单击Button后，GridView中我自己定义的TextBox和DropDownList就没有了。为什么？
问题二：
为什么GridView.DataSource == null？

if(!ispostback)是第一次加载时执行的,如果第二次加载则不再运行其中的程序.

#3

this.grdChapter.EnableViewState = true;

这句话就直接在gridview属性中直接设置就可以了,,这样你第一次所取的数据在你单击button后会自动保存的,,,,

gridview.datasource==null,因为你的页面刷新了,,,当然为null了..

呵呵..

#4

请问我的问题怎么解决呢！
我想在button onclick时间里面读取gridview每一行的DropDownList的值啊！

就像下面这个例子
http://blog.csdn.net/net_lover/archive/2006/09/13/1216855.aspx
要是放一个Button click一下，跟我遇到的问题一样，
怎么办啊！高手请帮忙!

#5

不要放在
if (!Page.IsPostBack) {}
里

#6

然后呢：）
不用IsPostBack 我试过，每个控件都会被重新创建初始化，这样还是不能得到填写的值啊

#7

每次綁定datagrid那麼dropdownlist邪說奧重新綁定一次的。

#1