如何从asp.net中的ArrayList值绑定ComboBox？

Question

但未填写正确

我还提到了这样的表和代码到图像

代码赞：

        DataTable dtUserType = new Common().GetUserType(true);
        DataTable dtUserType 1= new Common().GetUserTypeByUser(true);

        ArrayList lstUserTypeId =new ArrayList();
        lstUserTypeId.AddRange(dtUserType1.Rows[0]["UserTypeId"].ToString().Split(','));

        DataTable dtDownlist = new DataTable();
        dtDownlist.Columns.Add("UserTypeId");
        dtDownlist.Columns.Add("UserType");
        DataRow dr;


        foreach (string s in lstUserTypeId)
        {
            for (int i = 0; i < dtUserType.Rows.Count; i++)
            {

                dr = dtDownlist.NewRow();
                 //List Of superior List
                if(s.ToString() != dtUserType.Rows[i]["UserTypeId"].ToString())
                {


                    dr["USerType"] = dtUserType.Rows[i]["UserType"].ToString();
                    dr["UserTypeId"] = dtUserType.Rows[i]["UserTypeId"].ToString();
                    dtDownlist.Rows.Add(dr);
                }


            }
        }


        cmbUser.DataSource = dtDownlist; 
        cmbUser.DataTextField = "UserType";
        cmbUser.DataValueField = "UserTypeId";
        cmbUser.DataBind();

Answer 1

一般来说：

1. 不要将主表拆分为子表，每个子表有1列 - 这就是为什么表中有列的原因
2. 查询数据时 - 使用LINQ

3. 尽可能不使用DataTable - 观察我在答案中发布了多少个投射操作（在你的情况下使用类型表Common）

   DataTable common = new Common(); // Id, UserType, UserTypeId
   
   var sections = common.Where(c => c.UserType.ToString() == "B").First()
                        .ToString().Split(',');
   
   DataTable dtDownlist = new DataTable();
   dtDownlist.Columns.Add("UserTypeId");
   dtDownlist.Columns.Add("UserType");
   DataRow dr;
   
   
   foreach (string id in sections)
   {
       for (int i = 0; i < dtUserType.Rows.Count; i++)
       {
           if(Convert.ToInt16(id) == Convert.ToInt16(common.Rows[i]["Id"]))
           {
               dr = dtDownlist.NewRow();
   
               dr["USerType"] = dtUserType.Rows[i]["UserType"].ToString();
               dr["UserTypeId"] = dtUserType.Rows[i]["UserTypeId"].ToString();
               dtDownlist.Rows.Add(dr);
           }
       }
   }
   
   
   cmbUser.DataSource = dtDownlist; 
   cmbUser.DataTextField = "UserType";
   cmbUser.DataValueField = "UserTypeId";
   cmbUser.DataBind();