Question

我正在尝试编写一个只更新数据记录的代码。

我不需要能够更新行上的每个字段，只需更新一个特定字段。

我有一个定义GridView的页面如下：

<asp:Content runat="server" ID="BodyContent" ContentPlaceHolderID="MainContent">
<UpdatePanel> 
    <ContentTemplate>   
 <fieldset style="width: 1%">
        <legend>Search Customer</legend>
        <table>
            <tr>
                <td>
                <asp:DropDownList id="ddlSearchOption"
                    AutoPostBack="True"
                    OnSelectedIndexChanged="ddlSearchOption_SelectedIndexChanged"
                    runat="server">
                    <asp:ListItem Selected="True" Value="SearchBy"> Search By </asp:ListItem>
                    <asp:ListItem Value="CustID"> Customer ID </asp:ListItem>
                    <asp:ListItem Value="CustFirst"> First Name </asp:ListItem>
                    <asp:ListItem Value="CustLast"> Last Name </asp:ListItem>
                    <asp:ListItem Value="CustCity"> City </asp:ListItem>
                </asp:DropDownList>
                </td>
      <asp:Panel id="pnlCustSearch" runat="server" >
                    <td>
             <asp:Label id="lblEntry" runat="server" Text="" width="120px"></asp:Label>
                    </td>
                    <td>
                        <asp:TextBox id="txtSearchOptions" runat="server" width="50px">Hello</asp:TextBox>
                    </td>
                    <td>
                        <asp:Button id="btnFind" Text="Search" runat="server" onClick="btnFind_Click"></asp:Button>
                    </td>
    </asp:Panel>
            </tr>
        </table>
    </fieldset>
    <div id ="msg">
    <asp:Label id="lblMsg" runat="server" Text=""></asp:Label>
    </div>
    <div id="gridShow">

  <asp:GridView ID="GridView1" runat="server" GridLines="None" AutoGenerateColumns="false"
  AlternatingRowStyle-BackColor="#EEEEEE" EditRowStyle-BorderColor="Red">           
  <Columns>           
     <asp:TemplateField Visible="true" HeaderText="Customer ID">
        <ItemTemplate>
          <asp:Label runat="server" ID="lblCustID" Text='<%#Eval("CustID")%>' />
        </ItemTemplate>
     </asp:TemplateField>

     <asp:TemplateField HeaderText="First Name">

        <ItemTemplate>
         <asp:Label runat="server" ID="lblFirstName" Text='<%#Eval("CustFirstName") %>' />
        </ItemTemplate>
     </asp:TemplateField>
     <asp:TemplateField HeaderText="Last Name">
        <ItemTemplate>
          <asp:Label runat="server" ID="lblLastName" Text='<%#Eval("CustLastName") %>' />
        </ItemTemplate>
     </asp:TemplateField>

     <asp:TemplateField HeaderText="City">
       <ItemTemplate>
         <asp:Label runat="server" ID="lblCity" Text='<%#Eval("CustCity") %>' />
       </ItemTemplate>
     </asp:TemplateField>
     <asp:TemplateField HeaderText="Email">  
      <ItemTemplate>
         <asp:TextBox runat="server" ID="txtEmail" Text='<%#Eval("CustEmail") %>' />
          <asp:Button runat="server" ID="btnUpdate" Text="Update" onClick="GridView1_btnUpdate_Click"/>
  <asp:RequiredFieldValidator runat="server" ID="rfdCountry" ControlToValidate="txtEmail" 
             ValidationGroup="var1" ErrorMessage="*" />
       </ItemTemplate>
     </asp:TemplateField>

 </Columns>
 </asp:GridView>

</div>
</ContentTemplate>
</UpdatePanel> 

 </asp:Content>

然后在codebehind中我写下以下内容：

    protected void GridView1_btnUpdate_Click(Object sender, EventArgs e)
    {
       //Code goes here
    }

点击按钮更新电子邮件时没有任何反应。

我做错了什么？

我尝试使用其中一条建议：

        if (!IsPostBack)
        {
            GridView1.DataSource = App_Data.DataHandler.GetData("fname", "de");
            GridView1.DataBind();
            GridView1.Visible = true;
        }

显示数据，但点击事件无论如何都不起作用

我在GridView定义中添加了以下内容：

onrowcommand="GridView1_RowCommand"

并添加了建议的代码：

             <asp:Button runat="server" ID="btnUpdate" Text="Update" CommandName="UpdateEmail" 
             CommandArgument="<%# ((GridViewRow) Container).RowIndex %>"/>

在我的.cs文件中，我添加了以下内容：

        protected void GridView1_RowCommand(Object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "UpdateEmail")
        {
            //Get the index from the argument
            int index = Convert.ToInt32(e.CommandArgument);
            //Get the row
            GridViewRow row = GridView1.Rows[index];

            //Do whatever you need with your row here!
        }
    }

仍然，点击事件不会触发。

好的，这是.cs文件后面的代码：

public partial class index : System.Web.UI.Page
{
    protected override object LoadPageStateFromPersistenceMedium()
    {
        return Session["__VIEWSTATE"];
    }
    protected override void SavePageStateToPersistenceMedium(object viewState)
    {
        Session["VIEWSTATE"] = viewState;
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
            Reset();
        else
            lblMsg.Text = "";

    }

    protected void Reset()
    {
        pnlCustSearch.Visible = false;
        GridView1.Visible = false;
        lblMsg.Text = "";
    }

    protected void ddlSearchOption_SelectedIndexChanged(object sender, EventArgs e)
    {

            Reset();
            String ddlSelected = ddlSearchOption.SelectedValue;
            if (ddlSelected != "")
            {
                ViewState["ddlSelected"] = ddlSelected;
                pnlCustSearch.Visible = true;
                SelectLabel(ddlSelected);
            }
    }

    protected void SelectLabel(String choice)
    {
        switch (choice)
        {
            case "CustID":
                lblEntry.Text = "Enter Customer ID";
                break;
            case "CustFirst":
                lblEntry.Text = "Enter First Name";
                break;
            case "CustLast":
                lblEntry.Text = "Enter Last Name";
                break;
            case "CustCity":
                lblEntry.Text = "Enter City";
                break;
            default: 
                lblEntry.Text = "Enter Customer ID";
                break;
        }
    }

    protected void btnFind_Click(object sender, EventArgs e)
    {
        GridView1.Visible = true;
        String option = (String)ViewState["ddlSelected"];
        String input = txtSearchOptions.Text.Trim();

        GridView1.DataSource = DataHandler.GetData(option,input);
        GridView1.DataBind();
        GridView1.Visible = true;

    }

    protected void GridView1_RowCommand(Object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "UpdateEmail")
        {
            //Get the index from the argument
            int index = Convert.ToInt32(e.CommandArgument);
            //Get the row
            GridViewRow row = GridView1.Rows[index];

            //Do whatever you need with your row here!
        }
    }

    protected void btnUpdate_Click(Object sender, EventArgs e)
    {
        String txt = null;
        txt = "here";
    }
}

Answer 1

当您尝试处理来自GridView的事件时，您需要使用CommandName和CommandArgument然后处理来自RowCommand的{{1}}事件。

请参阅http://msdn.microsoft.com/...以供参考。

ASP.Net页面应如下所示：

GridView

在<asp:ButtonField runat="server" ID="btnUpdate" Text="Update" CommandName="UpdateEmail" CommandArgument="<%# CType(Container,GridViewRow).RowIndex %>" />事件中：

RowCommand

Answer 2

我终于明白了。我不得不将<asp:Button/>更改为

    `<asp:ButtonField Text="Update Email" CommandName="UpdateEmail"`

并将其从ItemTemplate中删除。

但为什么这是一个问题。我想要做的只是在带有按钮的同一项目模板中显示文本字段？

Answer 3

实际上，答案比我原先想的要容易得多。我只是使用不同的值来设置会话：__VIEWSTATE和VIEWSTATE

    protected override object LoadPageStateFromPersistenceMedium()
    {
        return Session["__VIEWSTATE"];
    }
    protected override void SavePageStateToPersistenceMedium(object viewState)
    {
    Session["VIEWSTATE"] = viewState;
    }

一旦我改变它，按钮就能够发射事件。

谢谢

按钮onClick不会在TemplateField内的GridView中触发

3 个答案: