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Asp.net DDL项目的定位?_Asp.net_Drop Down Menu - Fatal编程技术网

Asp.net DDL项目的定位?

Asp.net DDL项目的定位?,asp.net,drop-down-menu,Asp.net,Drop Down Menu,我有一个dropDownList,它从数据库中获取数据。现在,在数据绑定之后,我以编程方式向ddl添加另一个listItem,如下所示: protected void ddlEffects_DataBound(object sender, EventArgs e) { DropDownList ddl = dwNewItem.FindControl("ddlEffects") as DropDownList; ddl.Items.Add(new ListItem("","0"))

我有一个dropDownList,它从数据库中获取数据。现在,在数据绑定之后,我以编程方式向ddl添加另一个listItem,如下所示:

protected void ddlEffects_DataBound(object sender, EventArgs e)
{
    DropDownList ddl = dwNewItem.FindControl("ddlEffects") as DropDownList;
    ddl.Items.Add(new ListItem("","0")); //Adds an empty item so the user can select it and the item doesnt provide an effect
}
这一切都是可行的,但问题是新添加的listItem出现在DDL的底部。我想把它作为第一项。我尝试将值设为0,但仍处于底部。有没有办法把它放在最上面


谢谢

检查ddl.Items.Insert方法,该方法允许您在特定位置插入项

例如:

        using (Entities db = new Entities())
        {
            ddlDocumentTypes.DataSource = (from q in db.zDocumentTypes where (q.Active == true) select q);
            ddlDocumentTypes.DataValueField = "Code";
            ddlDocumentTypes.DataTextField = "Description";
            ddlDocumentTypes.DataBind();
            ddlDocumentTypes.Items.Insert(0, "--Select--");
            ddlDocumentTypes.Items[0].Value = "0";
        }

它使用EF为数据库加载包含项的DDL,然后在位置0处插入一个新项。

检查DDL.items.Insert方法,该方法允许您在特定位置插入项

例如:

        using (Entities db = new Entities())
        {
            ddlDocumentTypes.DataSource = (from q in db.zDocumentTypes where (q.Active == true) select q);
            ddlDocumentTypes.DataValueField = "Code";
            ddlDocumentTypes.DataTextField = "Description";
            ddlDocumentTypes.DataBind();
            ddlDocumentTypes.Items.Insert(0, "--Select--");
            ddlDocumentTypes.Items[0].Value = "0";
        }
它使用EF为数据库加载带有项的DDL,然后在位置0处插入一个新项