Question

我在UpdatePanel中有一个GridView，可以触发RowCommand事件。在触发RowCommand事件时，我将e.CommandArgument值分配给标签，但它不显示效果。我在执行期间在事件上设置了断点，它设置了标签文本属性，但在退出事件后，标签丢失了它的值并转到了之前的文本。我将值存储在ViewState和Session中但仍然无法正常工作。以下是我的代码。

这里的GridView1_RowCommand事件想要赋值给lblValue这是问题

protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
      if (e.CommandName == "Delete")
      {
            lblValue.Text = e.CommandArgument.ToString();
      }
}

这里我想通过标签值

从数据库中删除记录

    protected void Button2_Click(object sender, EventArgs e)
    {
        Int32 id = Convert.ToInt32(lblValue.Text);
        conn.RegionalBusinessUnits.Remove(conn.RegionalBusinessUnits.Where(rbu => rbu.Id == id).FirstOrDefault());
        conn.SaveChanges();
    }

这是标记

<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<div class="BoxStyle" >
    <div class="header"><asp:HyperLink ID="hlBack" runat="server"><img src="../images/back-icon.png" alt="Go Back" height="20" width="20" style="vertical-align: middle; text-align: center; cursor: pointer;" /></asp:HyperLink> &nbsp; Regional Department Unit List</div>

    <div id="myModal" class="reveal-modal">
        <h1>Delete</h1>
            <p>This will guide you through the delete process</p>
            <asp:Label ID="lblValue" runat="server" Text="Label"></asp:Label>
            <p><asp:Button ID="Button2" runat="server" Text="Button" OnClick="Button2_Click" /></p>
            <a class="close-reveal-modal">&#215;</a>
    </div>

    <div class="contents">
        <center>
            <asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
                <ContentTemplate>
                    <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
                    <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="RBUEntityDataSource" CssClass="gridview" OnRowCommand="GridView1_RowCommand" EnableViewState="False">
                        <Columns>
                            <asp:BoundField DataField="Id" HeaderText="Id" ReadOnly="True" SortExpression="Id" />
                            <asp:BoundField DataField="Region" HeaderText="Region" ReadOnly="True" SortExpression="Region" />
                            <asp:TemplateField HeaderText="Update">
                                <ItemTemplate>
                                    <asp:LinkButton ID="lbUpdate" runat="server" CommandName="Update" OnClick="lbUpdate_Click">Update</asp:LinkButton>
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:TemplateField HeaderText="Delete">
                                <ItemTemplate>
                                        <asp:LinkButton ID="lbDelete" class="big-link" data-reveal-id="myModal" runat="server" CommandName="Delete" CommandArgument='<%# Eval("Id") %>' OnClick="lbDelete_Click">Delete</asp:LinkButton>
                                </ItemTemplate>
                            </asp:TemplateField>
                        </Columns>
                    </asp:GridView>
                    <asp:EntityDataSource ID="RBUEntityDataSource" runat="server" ConnectionString="name=ChemonicsDBEntities" DefaultContainerName="ChemonicsDBEntities" EnableFlattening="False" EntitySetName="RegionalBusinessUnits" Select="it.[Id], it.[Region]" OrderBy="it.[Id] asc" Where="it.[DeletedBy] = 0">
                    </asp:EntityDataSource>
                </ContentTemplate>
                <Triggers>
                    <asp:AsyncPostBackTrigger ControlID="Button2" EventName="Click" />
                </Triggers>
            </asp:UpdatePanel>
        </center>
    </div>
    <div class="bottom"></div>
</div>

Answer 1

lblValue没有更新，因为它在UpdatePanel1之外。如果将带有ContentTemplate的UpdatePanel1直接移到ScriptManager下，它应该可以工作。

一定要确定

  </ContentTemplate>
</asp:UpdatePanel>

在最底层。

然后，您可以删除触发器并将UpdatePanel“UpdateMode”更改为“Always”

Answer 2

<asp:GridView runat="server" ID="gvDocuments" AutoGenerateColumns="false"
    AllowPaging="true" PageSize="10" DataKeyNames="DocumentID">                                      
<Columns>                                        

<asp:TemplateField HeaderText="Action">
    <ItemTemplate>                                                
        <asp:Button ID="btnDocumentViewAttachmentInGrid" runat="server" Text="View Attachment" CommandName="ViewAttachment" CausesValidation="false" />
    </ItemTemplate>
</asp:TemplateField>

</Columns>

</asp:GridView>

我的按钮单击我试图将文件流式传输到客户端，但得到错误“Microsoft JScript运行时错误：Sys.WebForms.PageRequestManagerParserErrorException：无法解析从服务器收到的消息。”因为我在更新面板上。我尝试注册datagridview进行回发，没有任何效果。最后，在代码中，我尝试了这个：

Protected Sub gvDocuments_RowCreated(sender As Object, e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles gvDocuments.RowCreated
    Try

        If (e.Row.RowType = DataControlRowType.DataRow) Then

            Dim btnDocumentViewAttachmentInGrid As Button = e.Row.FindControl("btnDocumentViewAttachmentInGrid")
            btnDocumentViewAttachmentInGrid.CommandArgument = e.Row.RowIndex.ToString()
            ScriptManager1.RegisterPostBackControl(btnDocumentViewAttachmentInGrid)

        End If




    Catch ex As Exception
        'handle error here
    End Try
End Sub

...然后我可以像这样传输文件：

Protected Sub gvDocuments_RowCommand(sender As Object, e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles gvDocuments.RowCommand
    Try

        If e.CommandName = "Select" Then
            gvDocuments.SelectedIndex = e.CommandArgument


        ElseIf e.CommandName = "ViewAttachment" Then


                Dim iDocumentID As Int64 = gvDocuments.DataKeys(e.CommandArgument).Value

                Dim oRows() As DataRow = dtDocs.Select("DocumentID = " & iDocumentID.ToString())
                If oRows.Length > 0 Then
                    Dim oRow As DataRow = oRows(0)

                    Dim strFileName As String = oRow("NetworkPath").ToString()

                    Dim strJustTheName As String = oRow("DocumentID").ToString() & "." & oRow("FileNameExtension").ToString()
                    strFileName &= strJustTheName


                    Response.Clear()
                    Response.ClearHeaders()
                    Response.ContentType = "application/octet-stream"
                    Response.AddHeader("Content-Disposition", String.Format("attachment;filename=""{0}""", strJustTheName))
                    Response.TransmitFile(strFileName)
                    Response.Flush()
                    Response.End()
                End If



        End If



    Catch ex As Exception
        'handle error
    End Try
End Sub

......和BOOM去炸药，完全奏效！：）

Answer 3

在这种情况下不是，但是可能是您向具有相同ID的GridView添加控件，您必须具有唯一的ID。我遇到了这个问题，并且有效

Answer 4

在Page_Load上必须像这样重新绑定gridview

If (!Page.IsPostBack) { bindhere() }

GridView rowcommand事件在updatepanel中不起作用

4 个答案: