关于DropDownList的问题

Question

现有两张表:
NewsClass 表字段 NewsID,NewsClassTxt
News 表字段 ID,NewsID,Title,NewTxt当修改新闻的时候,如果News.NewID = NewsClass.NewID 则DropDownList里对应的项被选中,在后台应该如何控制

Answer 1

DropDownList1.SelectedValue = "NewID";

Answer 2

foreach (ListItem li in DropDownList1.Items)
            {
                if (li.Value = NewsClass.NewID)
                {
                    li.Selected = true;
                }
            }

Answer 3

DropDownList1.SelectedValue = 要修改的新闻分类ID，即NewsID;

Answer 4

例子：前台：
<asp:DropDownList ID="DropDownList1" runat="server">
              <asp:ListItem Value="1">新闻1</asp:ListItem>
              <asp:ListItem Value="2">新闻2</asp:ListItem>
        </asp:DropDownList>
后台：
  DropDownList1.SelectedValue = "2"; //显示新闻2

Answer 5

查询NewsClass ，绑定NewsClass 到dropdownlist
DropDownList1.DataSource=ds;
DropDownList1.DataValueField="NewsID";
DropDownList1.DataTextField="NewsClassTxt ";
DropDownList1.DataBind();

Answer 6

<asp:Repeater ID="Repeater1" runat="server">
            <HeaderTemplate>
                <table>
            </HeaderTemplate>
            <ItemTemplate>
                <tr>
                    <td>
                        <%#Eval("id") %>
                    </td>
                    <td>
                        |</td>
                    <td>
                        <%#Eval("title") %>
                    </td>
                    </tr>
            </ItemTemplate>
            <FooterTemplate>
                </table></FooterTemplate>
        </asp:Repeater>

Answer 7

UP一楼的方法，可以直接读到NEWID

Answer 8

dropdownlist1.items.findbyvalue(newsid.tostring()).selected=true

Answer 9

DropDownList1.SelectedValue = "NewID";赞

Answer 10

DropDownList1.SelectedIndex= DropDownList1.items.IndexOf(DropDownList1.items.findbyvalue(newsid.tostring()));

Answer 11

DropDownList1.SelectedValue = "NewID";
一楼的就行。。

Answer 12

  if (News.NewID = NewsClass.NewID)
  {
      BJMember_CategoryProvince.Items.FindByText(News.NewID).Selected = true;
  }
or  if (News.NewID = NewsClass.NewID)
  {
      BJMember_CategoryProvince.Items.FindByText(News.NewID).Selected = true;
  }

Answer 13

说下我的这个
 public void ShowProvince()
    {
        //得到省级信息
        Province.Version = "cn";
        DataTable dt1 = WebManager.List(Province, "", "[ID],[Title]", "&version=", "[OrderNo] asc");
        DataView dv1 = new DataView(dt1);
        Province.ID = Member.CategoryProvince;
        WebManager.GetInfo(Province);        //BJMember_CategoryProvince.SelectedIndex=
        BJMember_CategoryProvince.DataSource = dv1;
        BJMember_CategoryProvince.DataValueField = "ID";
        BJMember_CategoryProvince.DataTextField = "Title";
        BJMember_CategoryProvince.DataBind();
        if (Province.Title!="")
        {
           //从数据库中取出来的省份信息不为空的话,就让dropdownlist的值为该省份的信息
            BJMember_CategoryProvince.Items.FindByText(Province.Title).Selected = true;
        }
      
        //根据省级信息得到市级信息        City.ParentID = Convert.ToInt32(BJMember_CategoryProvince.SelectedValue);
        City.ID = Member.CategoryFrom;
        City.ParentID = Convert.ToInt32(BJMember_CategoryProvince.SelectedValue);
        DataTable dt2 = WebManager.List(City, "", "[ID],[Title]", "&parentid=&id=", "[OrderNo]");
        DataView dv2 = new DataView(dt2);
        ////dv.Sort = " Path ";        BJMember_CategoryFrom.DataSource = dv2;
        BJMember_CategoryFrom.DataValueField = "ID";
        BJMember_CategoryFrom.DataTextField = "Title";
        BJMember_CategoryFrom.DataBind();
    }

Answer 14

DropDownList1.SelectedValue = 对应的NEWSID

Answer 15

查询NewsClass ，绑定NewsClass 到dropdownlist 
DropDownList1.DataSource=ds; 
DropDownList1.DataValueField="NewsID"; 
DropDownList1.DataTextField="NewsClassTxt "; 
DropDownList1.DataBind();

Answer 16

DropDownList1.SelectedValue = 要修改的新闻分类ID，即NewsID;

Answer 17

Dropdownlist直接设置selectvalue. 
不用这么遍历啦Checkboxlist,Listbox等倒是需要。。

Answer 18

26楼的说的对，直接设置selectvalue就可以了……

Answer 19

支持9楼的，用Item.FindByValue，这样如果下接框内没有符合条件的记录可以作对应的操作，如：insert一个当前值之类的。