Question

这是我的全网格

 <div id="grid">
    <asp:GridView ID="gridProduct"  runat="server" 
    AutoGenerateColumns="false"  
    ShowFooter="true" 
    onrowcancelingedit="gridProduct_RowCancelingEdit" 
    onrowdeleting="gridProduct_RowDeleting" onrowediting="gridProduct_RowEditing" 
    onrowupdating="gridProduct_RowUpdating" 
    onrowcommand="gridProduct_RowCommand"
    onrowdatabound="gridProduct_RowDataBound">
        <Columns>
            <asp:TemplateField>
            <EditItemTemplate>
                <asp:Button ID="buttonUpdate" CommandName="Update" runat="server" ToolTip="Update" Text="Update" />
                <asp:Button ID="buttonCancel" CommandName="Cancel" runat="server" ToolTip="Cancel" Text="Cancel" />
            </EditItemTemplate>

            <ItemTemplate>
                <asp:Button ID="buttonEdit" CommandName="Edit" runat="server" Text="Edit" ToolTip="Edit"/>
                <asp:Button ID="buttonDelete" CommandName="Delete" runat="server" Text="Delete" ToolTip="Delete"/>
            </ItemTemplate>
            <FooterTemplate>
                <asp:Button ID="buttonAdd" runat="server" Text="Ajouter" CommandName="AddNew" ToolTip="Add new User" ValidationGroup="validaiton" />
            </FooterTemplate>

            </asp:TemplateField>
            <asp:TemplateField HeaderText="#Piece">
            <EditItemTemplate>
            <asp:DropDownList ID="dropDownListPartsEdit" DataTextField="Nom" DataValueField="ID_AchatTemplate" runat="server" Text='<%#Eval("Piece") %>'/>
            </EditItemTemplate>
            <ItemTemplate>
            <asp:Label ID="labelItemPiece" runat="server" Text='<%#Eval("Piece") %>'/>
            </ItemTemplate>
            <FooterTemplate>
            <asp:DropDownList ID="dropDownListPartsFooter" runat="server" DataTextField="Nom" DataValueField="ID_AchatTemplate">
            </asp:DropDownList>   

            <%--<asp:TextBox ID="txtBoxPiece" runat="server"/>--%>
            <%--<asp:RequiredFieldValidator ID="fieldValidPiece" runat="server" ControlToValidate="txtBoxPiece" Text="*" ValidationGroup="validaiton"/>--%>
            </FooterTemplate> 

             </asp:TemplateField>
            <asp:TemplateField HeaderText="Series">
            <EditItemTemplate>
            <asp:TextBox ID="txtBoxEditSeries" runat="server" Text='<%#Eval("Series") %>'/>
            </EditItemTemplate>
            <ItemTemplate>
            <asp:Label ID="labelItemSeries" runat="server" Text='<%#Eval("Series") %>'/>
            </ItemTemplate>
            <FooterTemplate>
            <asp:TextBox ID="txtBoxSeries" runat="server"/>
            <asp:RequiredFieldValidator ID="fieldValidSeries" runat="server" ControlToValidate="txtBoxSeries" Text="*" ValidationGroup="validaiton"/>
            </FooterTemplate> 

             </asp:TemplateField>
            <asp:TemplateField HeaderText="Revision">
            <EditItemTemplate>
            <asp:TextBox ID="textBoxEditRevision" runat="server" Text='<%#Eval("Rev") %>'/>
            </EditItemTemplate>
            <ItemTemplate>
            <asp:Label ID="labelItemRevision" runat="server" Text='<%#Eval("Rev") %>'/>
            </ItemTemplate>
            <FooterTemplate>
            <asp:TextBox ID="txtBoxRevision" runat="server"/>
            <asp:RequiredFieldValidator ID="fieldValidRevision" runat="server" ControlToValidate="txtBoxRevision" Text="*" ValidationGroup="validaiton"/>
            </FooterTemplate> 

            </asp:TemplateField>
            <asp:TemplateField HeaderText="Firmware">
            <EditItemTemplate>
            <asp:TextBox ID="textBoxEditFirmware" runat="server" Text='<%#Eval("Firmware") %>'/>
            </EditItemTemplate>
            <ItemTemplate>
            <asp:Label ID="labelItemFirmware" runat="server" Text='<%#Eval("Firmware") %>'/>
            </ItemTemplate>
            <FooterTemplate>
            <asp:TextBox ID="txtBoxFirmware" runat="server"/>
            <asp:RequiredFieldValidator ID="fieldValidFirmware" runat="server" ControlToValidate="txtBoxFirmware" Text="*" ValidationGroup="validaiton"/>
            </FooterTemplate>

            </asp:TemplateField> 

           </Columns> 
    </asp:GridView>

这是我编辑的方法事件。首先，我尝试绑定我的dropDownList但是我收到错误“对象引用没有设置为对象的实例。”

       protected void gridProduct_RowEditing(object sender, GridViewEditEventArgs e)
    {



        ClientParts getclient = new ClientParts();

        ClientPartsSearchCriteria criteria = new ClientPartsSearchCriteria();


      ((DropDownList)gridProduct.Rows[e.NewEditIndex].FindControl("dropDownListPartsEdit")).DataSource = getclient.Get(criteria);


        ((DropDownList)gridProduct.Rows[e.NewEditIndex].FindControl("dropDownListPartsEdit")).DataBind();


        gridProduct.EditIndex = e.NewEditIndex;
        PsaDataSet psaList = (PsaDataSet)ViewState["psaList"];
        BindGrid(psaList, false);

    }

我不明白为什么“对象引用未设置为对象的实例”。从这一行

((DropDownList)gridProduct.Rows[e.NewEditIndex].FindControl("dropDownListPartsEdit")).DataSource = getclient.Get(criteria);

Answer 1

((DropDownList)gridProduct.Rows[e.NewEditIndex].FindControl("dropDownListPartsEd‌it")).DataSource = getclient.Get(criteria)

这是一段相当不安全的代码。首先，假设您的ClientParts.Get()方法返回正确的数据，其次，您假设FindControl()正在找到您的DropDownList。为了隔离哪个部分失败，将该行拆分为几行代码，并添加空检查。

我的c＃生锈了，但它应该是这样的（假设ClientParts.Get()返回DataTable）：

(DropDownList)ddlParts = ((DropDownList)gridProduct.Rows[e.NewEditIndex].FindControl("dropDownListPartsEd‌it"));
if (ddlParts != null)
{
    (DataTable)dtParts = getclient.Get(criteria);
    if (dtParts != null)
    {
        ddlParts.DataSource = dtParts;
        ddlParts.DataBind();
    }
}

编辑：问题是在此事件期间，您无法使用GridView.Rows [index] .FindControl（）引用EditItemTemplate控件。使用它将访问ItemTemplate中的控件。我不确定解决方法是什么，因为我从未试图以这种方式在模板中数据绑定控件。也许你应该考虑使用ObjectDataSource？

Answer 2

我必须将此下拉列入此onrowdatabound =“gridProduct_RowDataBound”＆gt; !!

带有DropDownList的GridView在编辑模式下抛出异常

2 个答案: