Question

使用Ado.net的内部联接无法正常运行。请参阅附带的代码并告诉我。我在“值”中成功接收字符串数组值。我想我的代码本身有一些问题。

public JsonResult searchdata(String[] values,String[] values1,String[] values2)
        {
            //String str;
            //for (int i = 0; i <= values.Length; i++)
            //{
            //    str = values[i];
            //    Console.WriteLine(str);
            //}

            using (SqlConnection connection = new SqlConnection("data source=.; database=Srivatsava; integrated security=SSPI"))
            {
                DataSet ds = new DataSet();
                connection.Open();
                SqlCommand cmd = connection.CreateCommand();
                String str= "select accntname,BU,salesop,isdormant from fourth_page as fg"+
                                  " INNER JOIN linked as ld on ld.productid=fg.productid"+
                                   "INNER JOIN isdormant as it on it.productid=ld.productid"+
                                   "where fg.accountname in" + values;
                cmd.CommandText = str;
                SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
                mySqlDataAdapter.SelectCommand = cmd;
                mySqlDataAdapter.Fill(ds);
                foreach (DataRow dr in ds.Tables[0].Rows)
                {
                    Console.WriteLine(dr[0].ToString() + "" + dr[1].ToString() + "" + Convert.ToInt32(dr[2]) + "" + Convert.ToBoolean(dr[3]));
                }               

                connection.Close();
            }
            return Json(values);

        }

Answer 1

values是一个数组，您无法将其注入查询。您需要从数组中读取每个项目并在in子句中使用它。以下代码应该可以正常工作。

我还用SqlDataReader替换了SqlDataAdapter来查询数据。

public JsonResult searchdata(String[] values)
{
    var result = new List<string>();
    using (var con = new SqlConnection("Put your conn string here"))
    {
        using (var cmd = new SqlCommand())
        {
           var str= "select accntname,BU,salesop,isdormant from fourth_page as fg"+
                            " INNER JOIN linked as ld on ld.productid=fg.productid"+
                            " INNER JOIN isdormant as it on it.productid=ld.productid ";


            if (values != null && values.Any())
            {
             var items = values.Select((x, counter) => "@v" + counter);
             str +=string.Format(" where fg.accountname in ({0})", 
                                                             string.Join(",", items));

                var paramCounter = 0;
                foreach (var value in values)
                {
                    cmd.Parameters.AddWithValue("@v" + paramCounter, value);
                    paramCounter++;
                }
            }
            cmd.CommandText = str;
            cmd.Connection = con;
            con.Open();
            var reader = cmd.ExecuteReader();
            if (reader.HasRows)
            {
                while (reader.Read())
                {
                    var c1 = reader.GetString(reader.GetOrdinal("accntname"));
                    result.Add(c1);
                }
            }                 
        }
    }
    return Json(result, JsonRequestBehavior.AllowGet);
}

使用ado.net的内部联接无法正常运行

1 个答案: