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我有一个页面，用户可以在 datalist 控件中选择不同的文档文件。使用 on pre-render 事件处理程序根据类别对文档进行分类。基于复选框控件（不是复选框列表）选择文档。到目前为止，一切都很好。我接下来要做的是在每个类别名称旁边放置一个“全选”复选框，该复选框应仅选择该类别下的复选框。这是数据列表控件：

<asp:DataList ID="DataList1" runat="server" RepeatDirection="Vertical" OnPreRender="DataList1_PreRender" DataKeyField="docid" EnableViewState="false">
<ItemTemplate>
    <table cellpadding="0" cellspacing="0" id="tbl_data">
        <tr>
            <td>
                <asp:Label ID="lblHeader" runat="server" Font-Bold="True" Font-Underline="True"></asp:Label>
             <asp:Label runat="server" id="lbl_cb_all" visible="false">Select All <input runat="server" id="cb_selectall" type="checkbox" value='<%# Eval("catid") %>' /> </asp:Label>
            </td>
        </tr>

        <tr runat="server" id="tr_data">
            <td>
                <asp:Label ID="lbl_categoryname" runat="server" Text='<%# Eval("categoryname") %>' Visible="false" /> <!-- Hide this; only used in Code Behind -->
                 <input runat="server" id="cb_docid" type="checkbox" value='<%# Eval("docid") %>' />
                  <asp:Hyperlink ID="hpl_docfileencr" Text='<%# Eval("docfileencr") %>' NavigateUrl='<%# "~/PDFEncr/" + DataBinder.Eval(Container.DataItem, "docfileencr") %>' Target="_blank"  runat="server" />
                <br />
            </td>
        </tr>
    </table>
</ItemTemplate>

这是 OnPreRender 代码：

protected void DataList1_PreRender(object sender, EventArgs e)
{
    string strTempLabelCategory = "";
    foreach (DataListItem item in DataList1.Items)
    {



        Label lbl_categoryname = item.FindControl("lbl_categoryname") as Label;


        if (strTempLabelCategory.ToUpper() != lbl_categoryname.Text.ToString().ToUpper())
        {
            strTempLabelCategory = lbl_categoryname.Text.ToString().ToUpper();
            Label lblHeader = item.FindControl("lblHeader") as Label;
            lblHeader.Text = strTempLabelCategory.ToUpper();

            Label lbltempdiv = item.FindControl("lbl_cb_all") as Label;
            lbltempdiv.Visible = true;
        }
    }
}

我一直在寻找可以在我的代码中工作但没有运气的东西。而且我对这段代码投入太多，现在无法尝试 Checkboxlist 控件（不确定这是否会有所帮助）。有任何想法吗？我想我可以使用：http ://www.dotnetcurry.com/ShowArticle.aspx?ID=77代码，但不知道如何使它工作？如果我能以某种方式使全选复选框与标签绑定，然后查找所有标签，那么链接的代码可能会有所帮助。谢谢！

4

3 回答 3

3
  1. 使用 HiddenFields 存储CatID和DocID
  2. 两者都使用 ASP.NET CheckBoxes 而不是 HTML-Inputs
  3. 处理 Check-All Checkbox'CheckedChanged事件：
protected void CheckAllChanged(Object sender, EventArgs e)
{
    CheckBox checkAll = (CheckBox)sender;
    DataListItem item = (DataListItem)checkAll.NamingContainer;
    HiddenField HiddenCatID = (HiddenField)item.FindControl("HiddenCatID");
    var catCheckBoxes = DataList1.Items.Cast<DataListItem>()
        .Where(li => ((HiddenField)li.FindControl("HiddenCatID")).Value == HiddenCatID.Value)
        .Select(li => li.FindControl("cb_docid"));
    foreach (CheckBox docCheckBox in catCheckBoxes)
    {
        docCheckBox.Checked = checkAll.Checked;
    }
}

在 aspx 上：

<asp:CheckBox runat="server" OnCheckedChanged="CheckAllChanged" AutoPostBack="true"  id="cb_selectall" />
<asp:HiddenField ID="HiddenCatID" runat="server" Value='<%# Eval("CatID") %>' />
<asp:HiddenField ID="HiddenDocID" runat="server" Value='<%# Eval("DocID") %>' />

您还需要EnableViewState=true在 DataList 上维护复选框状态并启用选中/取消选中。

编辑：

因为你有问题让它运行，这里有一个完整的工作示例页面。

这是 aspx 上所需的控件（注意 fe <tr runat="server" id="tr_category">)： 

<ItemTemplate>
    <table cellpadding="0" cellspacing="0" id="tbl_data">
        <tr runat="server" id="tr_category">
            <td>
                <asp:Label ID="lblHeader" runat="server" Font-Bold="True" Text='<%# Eval("categoryname") %>' Font-Underline="True"></asp:Label>
                <asp:Label runat="server" ID="lbl_cb_all">Select All
                <asp:CheckBox runat="server"  OnCheckedChanged="CheckAllChanged" AutoPostBack="true"  id="cb_selectall" />
                </asp:Label>
            </td>
        </tr>
        <tr runat="server" id="tr_data">
            <td>
                <asp:HiddenField ID="HiddenCatID" runat="server" Value='<%# Eval("CatID") %>' />
                <asp:CheckBox runat="server" id="cb_docid" />
                <asp:HyperLink ID="hpl_docfileencr" Text='<%# Eval("docfileencr") %>' NavigateUrl='<%# "~/PDFEncr/" + DataBinder.Eval(Container.DataItem, "docfileencr") %>'
                    Target="_blank" runat="server" />
                <br />
            </td>
        </tr>
    </table>
</ItemTemplate>

  1. 确保 DataList 仅是数据绑定if(!IsPostback)的，否则将不会维护复选框选择：

    protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack) BindDataList();
}

  2. 我正在使用ItemDataBound，而不是PreRender哪个对于正确重新加载 ViewState 很重要。我还简化了所有：

    protected void DataList1_ItemDataBound(Object sender, DataListItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType==ListItemType.AlternatingItem)
    {
        var row  = (DataRowView)e.Item.DataItem;
        var view = row.DataView;
        var lastRow = e.Item.ItemIndex == 0 ? null : view[e.Item.ItemIndex-1];
        var tr_category = (System.Web.UI.HtmlControls.HtmlTableRow)e.Item.FindControl("tr_category");
        var sameCategory = lastRow != null && (int)row["catid"] == (int)lastRow["catid"];
        tr_category.Visible = !sameCategory;
    }
}

  3. CheckAllChanged保持不变。

即使您选择了一个文档复选框并随后选择了一个类别复选框，这也会按预期工作，这会导致回发。

于 2012-04-06T20:03:52.340 回答
0

我想我可以通过对蒂姆的代码进行轻微修改来实现这一点。几点：我不得不为数据列表禁用 ViewState，否则，全选触发器不会保持选中框。我不明白为什么。此外，page_load 事件中没有 ispostback 检查，并且每次加载时都会绑定数据列表。我不是那是“最佳的”或不是。我还制作了两组 Asp:RadioButtons：CheckAll 和 CheckNone，而不是复选框。无论如何，这是相关的代码：

<asp:DataList ID="DataList1" runat="server" RepeatDirection="Vertical" DataKeyField="docid"
                EnableViewState="false" OnItemDataBound="DataList1_ItemDataBound">
                <ItemTemplate>
                    <table cellpadding="0" cellspacing="0" id="tbl_data">
                        <tr runat="server" id="tr_category">
                            <td>
                                <asp:Label ID="lblHeader" runat="server" Font-Bold="True" Text='<%# Eval("categoryname") %>'
                                    Font-Underline="True"></asp:Label>
                                <asp:Label runat="server" ID="lbl_cb_all">Select: All
                                    <asp:RadioButton runat="server" OnCheckedChanged="CheckAllChanged" AutoPostBack="true"
                                        ID="rb_selectall" GroupName="selectallnone" />
                                    | None
                                    <asp:RadioButton runat="server" OnCheckedChanged="CheckAllChangedNone" AutoPostBack="true"
                                        ID="rb_selectnone" GroupName="selectallnone" />
                                    <asp:HiddenField ID="HiddenCatID" runat="server" Value='<%# Eval("CatID") %>' />
                                    <asp:HiddenField ID="HiddenDocID" runat="server" Value='<%# Eval("docid") %>' />
                                </asp:Label>
                            </td>
                        </tr>
                        <tr runat="server" id="tr_data">
                            <td>
                                <asp:CheckBox runat="server" ID="cb_docid" Value='<%# Eval("docid") %>' />
                                <asp:HyperLink ID="hpl_docfileencr" Text='<%# Eval("docfileencr") %>' NavigateUrl='<%# "~/PDFEncr/" + DataBinder.Eval(Container.DataItem, "docfileencr") %>'
                                    Target="_blank" runat="server" />
                                <br />
                            </td>
                        </tr>
                    </table>
                </ItemTemplate>
            </asp:DataList>

 protected void DataList1_ItemDataBound(Object sender, DataListItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        var row = (DataRowView)e.Item.DataItem;
        var view = row.DataView;
        var lastRow = e.Item.ItemIndex == 0 ? null : view[e.Item.ItemIndex - 1];
        var tr_category = (System.Web.UI.HtmlControls.HtmlTableRow)e.Item.FindControl("tr_category");
        var sameCategory = lastRow != null && (int)row["catid"] == (int)lastRow["catid"];
        tr_category.Visible = !sameCategory;
    }
}

protected void CheckAllChanged(Object sender, EventArgs e)
{
    RadioButton checkAll = (RadioButton)sender;
    DataListItem item = (DataListItem)checkAll.NamingContainer;
    HiddenField HiddenCatID = (HiddenField)item.FindControl("HiddenCatID");

    var catCheckBoxes = DataList1.Items.Cast<DataListItem>()
        .Where(li => ((HiddenField)li.FindControl("HiddenCatID")).Value == HiddenCatID.Value)
        .Select(li => li.FindControl("cb_docid"))
        .ToList();
    foreach (CheckBox docCheckBox in catCheckBoxes)
    {
       // docCheckBox.Checked = checkAll.Checked;
        docCheckBox.Checked = true;
    }
 }

protected void CheckAllChangedNone(Object sender, EventArgs e)
{
    RadioButton checkAll = (RadioButton)sender;
    DataListItem item = (DataListItem)checkAll.NamingContainer;
    HiddenField HiddenCatID = (HiddenField)item.FindControl("HiddenCatID");

    var catCheckBoxes = DataList1.Items.Cast<DataListItem>()
        .Where(li => ((HiddenField)li.FindControl("HiddenCatID")).Value == HiddenCatID.Value)
        .Select(li => li.FindControl("cb_docid"))
        .ToList();

    foreach (CheckBox docCheckBox in catCheckBoxes)
    {
        docCheckBox.Checked = false;
    }


}

//订单按钮的部分代码如下；注意 HiddenField 的使用

 CheckBox cb = li.FindControl("cb_docid") as CheckBox;

        if (cb != null)
        {
            if (cb.Checked)
            {
                HiddenField docid = li.FindControl("HiddenDocID") as HiddenField;
                string dbcmd = @"Insert Into [order_details] (orderid,docid) Values (" + orderid + "," + docid.Value.ToString() + ")";
于 2012-04-08T13:27:56.717 回答
0 
 protected void chkAllN_CheckedChanged(object sender, EventArgs e)
    {
        lblSelectedRecord.InnerText = "0";
        /*this Foreach Loop performing for find gridview*/
        foreach (DataListItem dst in dstMulEmpSalInsert.Items)
        {
            GridView grd = (GridView)dst.FindControl("grdMulEmpSalInsert");
            CheckBox chk_All = (CheckBox)grd.HeaderRow.FindControl("chkAllN");

            if (chk_All.Checked == true)
            {
                /*this Foreach Loop performing for find gridview Controls*/
                foreach (GridViewRow gvr in grd.Rows)
                {
                    CheckBox chk_One = (CheckBox)gvr.FindControl("ChkSendOne");
                    

                    chk_One.Checked = true;
                    txt_Salary.ReadOnly = false;
                    lblSelectedRecord.InnerText = (Convert.ToInt32(lblSelectedRecord.InnerText) + 1).ToString();
                }
               

            }
            else
            {
                /*this Foreach Loop performing for find gridview Controls*/
                foreach (GridViewRow gvr in grd.Rows)
                {
                    CheckBox chk_One = (CheckBox)gvr.FindControl("ChkSendOne");
                    

                    chk_One.Checked = false;
                    

                }
                
            }
        }
        

    }
于 2020-10-17T08:47:19.923 回答