添加动态列一个ASP.NET的GridView [英] Adding dynamic columns to an ASP.NET Gridview
问题描述
我有一个问题，动态地添加列到GridView。我需要改变布局 - 即包含列 - 基于在DropDownList中的值。当用户在此列表中改变选择，我需要根据选择以除去所有未在第一列和动态地添加额外的列
I'm having a problem dynamically adding columns to a GridView. I need to change the layout -- i.e. the included columns -- based on the value in a DropDownList. When the user changes the selection in this list, I need to remove all but the first column and dynamically add additional columns based on the selection.
我在我的标记定义只有一个列 - 列0，一个模板列，在我宣布选择链接和其他应用程序的具体LinkButton的。这列需要永远存在。当ListBoxSelection制成，我删除所有，但第一列，然后重新添加所需的列（在此示例中，我已经简化它总是添加一个标题栏）。这里是code的一部分：
I have only one column defined in my markup -- column 0, a template column, in which I declare a Select link and another application specific LinkButton. That column needs to always be there. When the ListBoxSelection is made, I remove all but the first column and then re-add the desired columns (in this sample, I've simplified it to always add a "Title" column). Here is a portion of the code:
RemoveVariableColumnsFromGrid();
BoundField b = new BoundField();
b.DataField = "Title";
this.gvPrimaryListView.Columns.Add(b);
this.gvPrimaryListView.DataBind();
private void RemoveVariableColumnsFromGrid() {
int ColCount = this.gvPrimaryListView.Columns.Count;
//Leave column 0 -- our select and view template column
while (ColCount > 1) {
this.gvPrimaryListView.Columns.RemoveAt(ColCount - 1);
--ColCount;
}
}
第一次这样code贯穿而过，我看到两个静态列和动态添加职称一栏。然而，一个选择是由下一个时间，第一列中产生空的（在它没有）。我看到标题列，我看到的第一列在它的左边 - 但是有在它产生什么。在调试器，我可以看到，gvPrimaryListView确实仍然有两列和第一个（索引0）的确是一个模板列。事实上，柱甚至保留它的将在下面的标记设定为165像素（用于调试目的）宽度
The first time this code runs through, I see both the static column and the dynamically added "Title" column. However, the next time a selection is made, the first column is generated empty (nothing in it). I see the title column, and I see the first column to its left -- but there's nothing generated within it. In the debugger, I can see that gvPrimaryListView does indeed still have two columns and the first one (index 0) is indeed a template column. In fact, the column even retains it's width which is set as 165px in the markup below (for debugging purposes).
任何想法？
<asp:GridView ID="gvPrimaryListView" runat="server" Width="100%" AutoGenerateColumns="false"
DataKeyNames="Document_ID" EnableViewState="true" DataSourceID="odsPrimaryDataSource"
AllowPaging="true" AllowSorting="true" PageSize="10" OnPageIndexChanging="activeListView_PageIndexChanging"
AutoGenerateSelectButton="False" OnSelectedIndexChanged="activeListView_SelectedIndexChanged"
Visible="true" OnRowDataBound="CtlDocList_RowDataBound" Font-Size="8pt" Font-Names="Helvetica">
<Columns>
<asp:TemplateField ShowHeader="false">
<ItemTemplate>
<asp:LinkButton EnableTheming="false" ID="CtlSelectDocRowBtn" runat="server" Text="Select"
CommandName="Select" CssClass="gridbutton" OnClick="RowSelectBtn_Click" />
<asp:ImageButton EnableTheming="false" ID="DocViewBtn" runat="server" ImageUrl="../../images/ViewDoc3.png"
CssClass="gridbutton" CommandName="Select" OnClick="DocViewBtn_Click" />
</ItemTemplate>
<ItemStyle Width="165px" />
</asp:TemplateField>
</Columns>
<EmptyDataTemplate>
<asp:Label ID="Label6" runat="server" Text="No rows found." SkinID="LabelHeader"></asp:Label>
</EmptyDataTemplate>
</asp:GridView>
只是一些额外的信息。
Just some additional information.
它无关的事实，这是第一列，但一切都做的事实，这是一个TemplateField。如果我把一个正常的列向左（在标记）和模板列列向右移，第一列呈现罚款和（现二）模板列列消失。
It has nothing to do with the fact that it is the first column but everything to do with the fact that it is a TemplateField. If I put a normal column to the left (in the markup) and shift the TemplateField column to the right, the first column renders fine, and the (now second) TemplateField column disappears.
另一个奇怪的事情 - 这个问题不会发生第一回发 - 或第二 - 但它开始在第三回发，然后继续进行后续的回传。我难倒。
Another strange thing -- the problem doesn't happen the first postback -- OR THE SECOND -- but it starts on the third postback and then continues for subsequent postbacks. I'm stumped.
推荐答案
最近，我征服了，在GridView的动态列silmilar问题，这或许会有所帮助。
I recently conquered silmilar issues with dynamic columns in gridviews, perhaps this will help.
首先将视图状态关闭结果
其次编程添加列在OnInit事件发射功能结果
最后我用下面的辅助类造成的复选框实例时RowDataBound事件拉开序幕。有一些很难codeD。
First turn the viewstate off
Second add the columns programatically in a function fired in the oninit event
Lastly I used the following helper class to cause the checkboxes to instantiate when the RowDataBound event kicked off. Yes some of it is hard coded.
这里到底是所有code。有它:)作为信息披的是，等等等等...
Heck here is all the code. Have at it :) Warrenty as is, blah blah blah...
最后，因为我刚开始我的脚湿DOTNET的任何提示会pciated AP $ P $ [IE不宰我太多:)。是的借的初始$ C $从带C的地方，对不起，我不记得了我的头顶：（
Finally since I am just getting my feet wet DotNet any tips would be appreciated [IE don't rip me too much :) ]. And yes 'borrowed' the initial code from the web somewhere, sorry I cant remember off the top of my head :(
- 消防这一关在保护覆盖无效的OnInit
-- Fire this off in protected override void OnInit
private void GridViewProject_AddColumns()
{
DataSet dsDataSet = new DataSet();
TemplateField templateField = null;
try
{
StoredProcedure sp = new StoredProcedure("ExpenseReportItemType_GetList", "INTRANETWEBDB", Context.User.Identity.Name);
dsDataSet = sp.GetDataSet();
if (sp.RC != 0 && sp.RC != 3000)
{
labelMessage.Text = sp.ErrorMessage;
}
int iIndex = 0;
int iCount = dsDataSet.Tables[0].Rows.Count;
string strCategoryID = "";
string strCategoryName = "";
iStaticColumnCount = GridViewProject.Columns.Count;
// Insert all columns immediatly to the left of the LAST column
while (iIndex < iCount)
{
strCategoryName = dsDataSet.Tables[0].Rows[iIndex]["CategoryName"].ToString();
strCategoryID = dsDataSet.Tables[0].Rows[iIndex]["CategoryID"].ToString();
templateField = new TemplateField();
templateField.HeaderTemplate = new GridViewTemplateExternal(DataControlRowType.Header, strCategoryName, strCategoryID);
templateField.ItemTemplate = new GridViewTemplateExternal(DataControlRowType.DataRow, strCategoryName, strCategoryID);
templateField.FooterTemplate = new GridViewTemplateExternal(DataControlRowType.Footer, strCategoryName, strCategoryID);
// Have to decriment iStaticColumnCount to insert dynamic columns BEFORE the edit row
GridViewProject.Columns.Insert((iIndex + (iStaticColumnCount-1)), templateField);
iIndex++;
}
iFinalColumnCount = GridViewProject.Columns.Count;
iERPEditColumnIndex = (iFinalColumnCount - 1); // iIndex is zero based, Count is not
}
catch (Exception exception)
{
labelMessage.Text = exception.Message;
}
}
- 助手类
public class GridViewTemplateExternal : System.Web.UI.ITemplate
{
#region Fields
public DataControlRowType DataRowType;
private string strCategoryID;
private string strColumnName;
#endregion
#region Constructor
public GridViewTemplateExternal(DataControlRowType type, string ColumnName, string CategoryID)
{
DataRowType = type; // Header, DataRow,
strColumnName = ColumnName; // Header name
strCategoryID = CategoryID;
}
#endregion
#region Methods
public void InstantiateIn(System.Web.UI.Control container)
{
switch (DataRowType)
{
case DataControlRowType.Header:
// build the header for this column
Label labelHeader = new Label();
labelHeader.Text = "<b>" + strColumnName + "</b>";
// All CheckBoxes "Look Up" to the header row for this information
labelHeader.Attributes["ERICategoryID"] = strCategoryID;
labelHeader.Style["writing-mode"] = "tb-rl";
labelHeader.Style["filter"] = "flipv fliph";
container.Controls.Add(labelHeader);
break;
case DataControlRowType.DataRow:
CheckBox checkboxAllowedRow = new CheckBox();
checkboxAllowedRow.Enabled = false;
checkboxAllowedRow.DataBinding += new EventHandler(this.CheckBox_DataBinding);
container.Controls.Add(checkboxAllowedRow);
break;
case DataControlRowType.Footer:
// No data handling for the footer addition row
CheckBox checkboxAllowedFooter = new CheckBox();
container.Controls.Add(checkboxAllowedFooter);
break;
default:
break;
}
}
public void CheckBox_DataBinding(Object sender, EventArgs e)
{
CheckBox checkboxAllowed = (CheckBox)sender;// get the control that raised this event
GridViewRow row = (GridViewRow)checkboxAllowed.NamingContainer;// get the containing row
string RawValue = DataBinder.Eval(row.DataItem, strColumnName).ToString();
if (RawValue.ToUpper() == "TRUE")
{
checkboxAllowed.Checked = true;
}
else
{
checkboxAllowed.Checked = false;
}
}
#endregion
}
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