Question

我有一个工作正常的gridview，但是给我一个错误“编辑单击时对象未设置为对象的实例。

我相信是因为我的gridview中的标签在编辑模式下为空，这是导致问题的原因，但我不知道如何解决这个问题。

              <asp:BoundField DataField="Received" HeaderText="Received" SortExpression="Received"
                        ReadOnly="true">
                        <ItemStyle HorizontalAlign="Center" />
                    </asp:BoundField>
                    <asp:TemplateField HeaderText="Complete" SortExpression="Complete">                            
                        <ItemTemplate>
                            <asp:Label ID="lblComplete" runat="server" Text='<%# Bind("Complete") %>'></asp:Label>
                        </ItemTemplate>
                        <ItemStyle HorizontalAlign="Center" />
                    </asp:TemplateField>
                    <asp:BoundField DataField="TransTime" HeaderText="Trans. Time" SortExpression="TransTime"
                        ReadOnly="true">
                        <ItemStyle HorizontalAlign="Center" />
                    </asp:BoundField>
                    <asp:TemplateField ShowHeader="False">
                        <ItemTemplate>
                            <asp:LinkButton ID="lbClose" runat="server" CausesValidation="False" CommandName="CloseClicked" Text ="Close"
                                OnClick="CloseClick_Click">Close</asp:LinkButton>
                            <asp:LinkButton ID="lbEdit" runat="server" CausesValidation="False" CommandName="EditRow"  Text =""
                                OnClick="Edit_Click" CommandArgument='<%# Eval("TicketId")%>'>Edit</asp:LinkButton>
                            <asp:LinkButton ID="lbDelete" runat="server" CausesValidation="False" CommandName="DeleteRow"  Text =""
                                OnClick="Delete_Click">Delete </asp:LinkButton>


                        </ItemTemplate>
                        <EditItemTemplate>
                            <asp:LinkButton ID="lbUpdate" runat="server" CausesValidation="True" CommandName="UpdateRow"
                                ForeColor="White" Text="Update" CommandArgument='<%# Eval("TicketId")%>'></asp:LinkButton>
                            <asp:LinkButton ID="lbCancel" runat="server" CausesValidation="False" CommandName="CancelUpdate"
                                ForeColor="White" CommandArgument='<%# Eval("TicketId")%>' Text="Cancel"></asp:LinkButton>
                        </EditItemTemplate>
                        <FooterStyle HorizontalAlign="Center" />
                        <ItemStyle HorizontalAlign="Center" />
                    </asp:TemplateField>
                </Columns>
                <EditRowStyle BackColor="#999999" />
                 />

            </asp:GridView>

RowCommand

    protected void gvData_RowCommand(object sender, GridViewCommandEventArgs e)
    {
           if (e.CommandName == "EditRow")
           {
               //This enables the EditTemplate
               int rowindex = ((GridViewRow)             ((LinkButton)e.CommandSource).NamingContainer).RowIndex;
                gvData.EditIndex = rowindex; //Enables the edit row in gridview                      
            }
    }

我在lbClose.Enabled

中收到错误

  protected void gvData_RowDataBound(object sender, GridViewRowEventArgs e)
 {
e.Row.Cells[0].Visible = false; 

if (e.Row.RowType == DataControlRowType.DataRow)
{
    LinkButton lbClose = (LinkButton)e.Row.Cells[5].FindControl("lbClose");
    LinkButton lbEdit = (LinkButton)e.Row.Cells[5].FindControl("lbEdit");
    LinkButton lbDelete = (LinkButton)e.Row.Cells[5].FindControl("lbDelete");


    var lblTrans = (Label)e.Row.FindControl("lblTrans");
    var lblComplete = (Label)e.Row.FindControl("lblComplete");               


    if (e.Row.Cells[3].Text == "")
    {
        lbClose.Enabled = true; //Error Here
        lbEdit.Enabled = true;
        lbDelete.Enabled = true;
    }
    else
    {
        lbClose.Enabled = false;
    }                       
}
}

Answer 1

我相信是因为我在gridview中的标签在编辑模式下为空，这就是导致问题的原因......

好的，所以你说当你在这一行输入EditMode时会出现问题。你是对的，这些控件在EditMode中不存在，因为它们是ItemTemplate的一部分。所以这样做：

LinkButton lbClose = (LinkButton)e.Row.Cells[5].FindControl("lbClose");
if (lbClose == null) { return; }

如果找不到控件，就会知道行的状态，因此下面的语句无关紧要。

Answer 2

EditMode中不存在这些控件，因为它们是ItemTemplate的一部分。只是改变条件！

if (e.Row.RowType == DataControlRowType.DataRow & gvData.EditIndex != e.Row.RowIndex)

RowDataBound对象未设置为对象的实例

2 个答案: