Question

GridView与DropDownList结合使用的一个问题？求解

我在GridView的ItemTemplate中放了一个DropDownList，选项有“男”“女”，想要达到的效果是绑定时，从数据库读取字段sex的值为“男”时，DropDownList的“男”选项被选中，否则选项“女”被选中。我在RowDataBound里写了如下代码，发现只能读取到数据表的第一行数据，不知道怎么改？
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType==DataControlRowType.DataRow)
{
string sqlSel = "select * from student";
DataTable dt = gl.getDataTable(sqlSel);
string gender = dt.Rows[0].ItemArray[2].ToString();
DropDownList ddl = (DropDownList)e.Row.Cells[2].FindControl("DropDownList1");
if (gender.Trim().Equals("男"))
ddl.SelectedValue = "0";
else
ddl.SelectedValue = "1";
}
}
其中getDataTable()是一个公共类的方法，那个没有问题的。另外，我试过循环遍历各个数据行，但是结果还是显示出来的效果都只有一个选项被选中。望赐教！！

Answer 1

你的逻辑有问题

string gender = dt.Rows[0].ItemArray[2].ToString();
==
也就是说每次得到的性别都是第一行第三个字段的值，也就是说你永远取的是第一行的数据

而你想做的事情是查询某个指定学生的性别，所以你的sql语句最起码也是 select * from student where id = ...这样

由于不知道你其他的代码，无法帮助修改
==
我还以为上面的代码是楼主贴的... 汗啊

前台.aspx
<asp:GridView ID="GridView1" runat="server" AllowSorting="True" AutoGenerateColumns="False"
Font-Size="9pt" onrowdatabound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="身份证号码" HeaderText="用户ID" SortExpression="身份证号码" />
<asp:BoundField DataField="姓名" HeaderText="用户姓名" SortExpression="姓名" />
<asp:TemplateField HeaderText="员工性别">
<ItemTemplate>
<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem Value="男">男</asp:ListItem>
<asp:ListItem Value="女">女</asp:ListItem>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="家庭住址" HeaderText="家庭住址" SortExpression="家庭住址" />
</Columns>
</asp:GridView>

后台.aspx.cs
public partial class Default4 : System.Web.UI.Page
{
SqlConnection sqlcon;
string strCon = "Data Source=(local);Database=北风贸易;Uid=sa;Pwd=sa";
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string sqlstr = "select top 5 * from 飞狐工作室";
sqlcon = new SqlConnection(strCon);
SqlDataAdapter myda = new SqlDataAdapter(sqlstr, sqlcon);
DataSet myds = new DataSet();
sqlcon.Open();
myda.Fill(myds, "飞狐工作室");
sqlcon.Close();
GridView1.DataSource = myds;
//这里对应表的主键
GridView1.DataKeyNames = new string[] { "身份证号码" };
GridView1.DataBind();
}
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DropDownList ddl = e.Row.FindControl("DropDownList1") as DropDownList;

if (ddl != null)
{
string sqlstr = "select top 1 员工性别 from 飞狐工作室 where 身份证号码 = @id";
SqlConnection cn = new SqlConnection(strCon);
SqlCommand cmd = new SqlCommand(sqlstr, cn);
cmd.Parameters.AddWithValue("@id", (e.Row.DataItem as DataRowView)["身份证号码"]);
cn.Open();
string value = (string)cmd.ExecuteScalar();
cn.Close();

ListItem item = ddl.Items.FindByText(value);
if (item != null)
{
item.Selected = true;
}
}
}
}
}

Answer 2

后台代码：
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
public partial class Default4 : System.Web.UI.Page
{
SqlConnection sqlcon;
string strCon = "Data Source=(local);Database=北风贸易;Uid=sa;Pwd=sa";
protected void Page_Load(object sender, EventArgs e)
{
DropDownList ddl;
if (!IsPostBack)
{
string sqlstr = "select top 5 * from 飞狐工作室";
sqlcon = new SqlConnection(strCon);
SqlDataAdapter myda = new SqlDataAdapter(sqlstr, sqlcon);
DataSet myds = new DataSet();
sqlcon.Open();
myda.Fill(myds, "飞狐工作室");
GridView1.DataSource = myds;
GridView1.DataBind();
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
DataRowView mydrv = myds.Tables["飞狐工作室"].DefaultView[i];
if (Convert.ToString(mydrv["员工性别"]).Trim() == "True")
{
ddl = (DropDownList)GridView1.Rows[i].FindControl("DropDownList1");
ddl.SelectedIndex = 0;
}
if (Convert.ToString(mydrv["员工性别"]).Trim() == "False")
{
ddl = (DropDownList)GridView1.Rows[i].FindControl("DropDownList1");
ddl.SelectedIndex = 1;
}
}
sqlcon.Close();
}
}
public SqlDataReader ddlbind()
{
string sqlstr = "select distinct 员工性别 from 飞狐工作室";
sqlcon = new SqlConnection(strCon);
SqlCommand sqlcom = new SqlCommand(sqlstr, sqlcon);
sqlcon.Open();
return sqlcom.ExecuteReader();
}

前台主要代码：
<asp:GridView ID="GridView1" runat="server" AllowSorting="True" AutoGenerateColumns="False"
CellPadding="3" Font-Size="9pt" BackColor="White" BorderColor="#CCCCCC" BorderStyle="None" BorderWidth="1px">
<FooterStyle BackColor="White" ForeColor="#000066" />
<Columns>
<asp:BoundField DataField="身份证号码" HeaderText="用户ID" SortExpression="身份证号码" />
<asp:BoundField DataField="姓名" HeaderText="用户姓名" SortExpression="姓名"/>
<asp:TemplateField HeaderText="员工性别">
<ItemTemplate>
<asp:DropDownList ID="DropDownList1" runat="server" DataSource='<%# ddlbind()%>' DataValueField="员工性别" DataTextField="员工性别">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="家庭住址" HeaderText="家庭住址" SortExpression="家庭住址"/>

</Columns>
<RowStyle ForeColor="#000066" />
<SelectedRowStyle BackColor="#669999" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="White" ForeColor="#000066" HorizontalAlign="Left" />
<HeaderStyle BackColor="#006699" Font-Bold="True" ForeColor="White" />
</asp:GridView>