C# 在当前行的下拉列表中选择新值时未更新Gridview数据库

我有一个四列的gridview。前三个是绑定字段STARTENDYEAR、ENDYEAR和IDENTIFIER，第三个是dropdownCHANGE。下拉列表的目的是更改标识符字段的值。前三列从一个oracle表中获取。每个STARTENDYEAR都有一个适用于它的标识符值列表。这些适用值在另一个表中提供。这些值已成功获取并填充到下拉列表中。我正在使用ASP.NET和C

要求：每当用户从下拉列表中选择不同的值时，gridview和后端表都需要使用新的标识符值进行更新

到目前为止已实现：下拉列表已填充第二个表中的适用值列表。每当用户选择新值时，我都能够在后端代码中捕获新值

问题：无法使用获取的新标识符值更新gridview和数据库。我怀疑这可能是一个数据绑定问题，它阻止了sql update查询在后端C代码上成功触发

ASP代码：

C代码：

---

}

必须在OracleCommand对象上调用ExecuteOnQuery才能在base中执行指令

找到一条路 我遇到了同样的问题，在gridview的编辑模板字段中有一个下拉列表。下拉列表中的值更改不会影响更新过程。我已经通过以下步骤解决了这个问题。1.检查“RowUpdate”事件中下拉列表返回的值。该值应为您选择的下拉列表的精确值

使用下拉列表中的值查找并更改字段的值。就这样。。。例如，行更新事件如下所示。。 `受保护的无效GridView1\u行更新对象发送方，GridViewUpdateEventArgs e {

DropDownList dr=DropDownListGridView1.Rows[e.RowIndex].FindControlDropYearEdit；字符串st=dr.SelectedValue； 字符串sr=dr.SelectedItem.Text

//手动更改必填字段的内部值 e、 新值[年]=st； }`

---

现在，更改的值将进入数据库。

感谢您的回复。我在使用建议的修改运行网页时遇到了一个问题。在我从下拉列表中选择一个不同的值后，网页显示等待localhost很长时间。我没有更新gridview和数据库，这有很多原因。是否在DropDownList\u SelectedIndexChanged方法上放置断点？

<%@ Page Title="Database" Language="C#" MasterPageFile="~/Site.master"    AutoEventWireup="true"
CodeFile="Database.aspx.cs" Inherits="About" %>

 <asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
 </asp:Content>
 <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">

 <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
 DataSourceID="SqlDataSource2" onrowdatabound="GridView1_RowDataBound1" DataKeyNames="IDENTIFIER">
        <Columns>
             <asp:BoundField DataField="STARTENDYEAR" HeaderText="STARTENDYEAR" 
                SortExpression="STARTENDYEAR" />
            <asp:BoundField DataField="ENDYEAR" HeaderText="ENDYEAR" SortExpression="ENDYEAR" />
            <asp:BoundField DataField="IDENTIFIER" HeaderText="IDENTIFIER" 
                SortExpression="IDENTIFIER" />
            <asp:TemplateField HeaderText="CHANGE" SortExpression="CHANGE"> 
                <ItemTemplate> 
                    <asp:DropDownList ID="DropDownList1" runat="server" DataTextField="CODE" DataValueField="CODE" 
                    OnSelectedIndexChanged="DropDownList_SelectedIndexChanged" AutoPostBack="True"> 
                    </asp:DropDownList> 
                </ItemTemplate> 
            </asp:TemplateField> 
        </Columns>
    </asp:GridView>

     <asp:SqlDataSource ID="SqlDataSource2" runat="server" 
        ConnectionString="<%$ ConnectionStrings:RonSql %>" 
        ProviderName="<%$ ConnectionStrings:RonSql.ProviderName %>"
    SelectCommand="select STARTENDYEAR, ENDYEAR, IDENTIFIER from R70A109 where (STATE = :SegState) order by STARTENDYEAR, ENDYEAR">

         <SelectParameters>
            <asp:SessionParameter Name="SegState" SessionField="SegState" DefaultValue="0" />

         </SelectParameters>               


    </asp:SqlDataSource>

    <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
        ConnectionString="<%$ ConnectionStrings:RonSql %>" 
        ProviderName="<%$ ConnectionStrings:RonSql.ProviderName %>"> 


    </asp:SqlDataSource>

public partial class About : System.Web.UI.Page
{
        protected void GridView1_RowDataBound1(object sender, GridViewRowEventArgs e)
        {          DataRowView CurrentRow = (DataRowView)e.Row.DataItem;
         if (e.Row.RowType == DataControlRowType.DataRow)
         {
             int StartYear = Convert.ToInt32(CurrentRow["StartYear"].ToString());

        if (StartYear > 2005)
            StartYear = 2005;

            DataTable dtcodes = GetByState(StartYear);

            DropDownList CurrentDropDown = (DropDownList)e.Row.FindControl("DropDownList1");
            CurrentDropDown.DataSource = dtcodes;
            CurrentDropDown.DataBind();

    }
}




 protected void DropDownList_SelectedIndexChanged(object sender, EventArgs e)
{

   DropDownList SelectedDropDown = (DropDownList)sender;
   GridViewRow SelectedRow = (GridViewRow)SelectedDropDown.NamingContainer;
   int StartYear = Convert.ToInt32(SelectedRow.Cells[0].Text);
   int EndYear = Convert.ToInt32(SelectedRow.Cells[1].Text);
   int IdentifierOld = Convert.ToInt32(SelectedRow.Cells[2].Text);
   int IdentifierNew =  Convert.ToInt32(SelectedDropDown.SelectedItem.Value);


   if (StartYear < 2005)
   {
       string ConString = "Data Source=ORACLE;User ID=****;Password=****";
       string CodeUpdate = "update R70A109 set IDENTIFIER = :New_Identifier where StartYear = :StartYear) AND (EndYear = :EndYear) AND (IDENTIFIER = :Old_Identifier)";
       OracleConnection con = new OracleConnection(ConString);
       con.Open();
       OracleCommand SqlCodeUpdate = new OracleCommand(CodeUpdate, con);
       SqlCodeUpdate.Parameters.Add(new OracleParameter("@New_Identifier", IdentifierNew));
       SqlCodeUpdate.Parameters.Add(new OracleParameter("@StartYear", StartYear));
       SqlCodeUpdate.Parameters.Add(new OracleParameter("@EndYear", EndYear));
       SqlCodeUpdate.Parameters.Add(new OracleParameter("@Old_Identifier", IdentifierOld));
       OracleDataAdapter DatAdpt = new OracleDataAdapter();
       DatAdpt.UpdateCommand = SqlCodeUpdate;
        con.Close();

    }
}

if (StartYear < 2005)
   {
       string ConString = "Data Source=ORACLE;User ID=****;Password=****";
       string CodeUpdate = "update R70A109 set IDENTIFIER = :New_Identifier where StartYear = :StartYear) AND (EndYear = :EndYear) AND (IDENTIFIER = :Old_Identifier)";
       using (OracleConnection con = new OracleConnection(ConString))
       {
            OracleCommand SqlCodeUpdate = new OracleCommand(CodeUpdate, con);
            SqlCodeUpdate.Parameters.Add(new OracleParameter("@New_Identifier", IdentifierNew));
            SqlCodeUpdate.Parameters.Add(new OracleParameter("@StartYear", StartYear));
            SqlCodeUpdate.Parameters.Add(new OracleParameter("@EndYear", EndYear));
            SqlCodeUpdate.Parameters.Add(new OracleParameter("@Old_Identifier", IdentifierOld));
            SqlCodeUpdate.Connection.Open();
            SqlCodeUpdate.ExecuteNonQuery();
       }

    }
...