引用的列不在範圍內：''

Question

你好我仍然是新手在linq和編程 我試圖使用水晶報告與linq查詢並將其放入數據表中我使用的函數拋出，但得到列引用不在範圍內：''..

我想加入3個表。

這是我從網上找到了一個功能

public DataTable LINQToDataTable<T>(IEnumerable<T> varlist) 
     { 
      DataTable dtReturn = new DataTable(); 

      // column names 
      PropertyInfo[] oProps = null; 

      if (varlist == null) return dtReturn; 

      foreach (T rec in varlist) 
      { 
       // Use reflection to get property names, to create table, Only first time, others will follow 
       if (oProps == null) 
       { 
        oProps = ((Type)rec.GetType()).GetProperties(); 
        foreach (PropertyInfo pi in oProps) 
        { 
         Type colType = pi.PropertyType; 

         if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition() 
         == typeof(Nullable<>))) 
         { 
          colType = colType.GetGenericArguments()[0]; 
         } 

         dtReturn.Columns.Add(new DataColumn(pi.Name, colType)); 
        } 
       } 

       DataRow dr = dtReturn.NewRow(); 

       foreach (PropertyInfo pi in oProps) 
       { 
        dr[pi.Name] = pi.GetValue(rec, null) == null ? DBNull.Value : pi.GetValue 
        (rec, null); 
       } 

       dtReturn.Rows.Add(dr); 
      } 
      return dtReturn; 
     } 

，這裏是我的LINQ

var id = (from u in myDb.TBL_TRANSAKSI_MKN_MNMs 
        join l in myDb.TBL_DETAIL_TRANSAKSIs on u.ID_NOTA equals l.ID_NOTA 
        //into g1 
        join m in myDb.TBL_MKN_MNMs on l.ID_MKN_MNM equals m.ID_MKN_MNM 
        //into g 

        group new {u,l,m} by new {u.TGL_TRANSAKSI, m.NAMA_MKN_MNM, m.HARGA_JUAL, l.ID_MKN_MNM, u.USERNAME}      
        into grp 

        where grp.Key.TGL_TRANSAKSI.Value.Date.Equals(dateTimePicker1.Value.Date) 

        select new 
        { 
         MakanMinum = grp.Key.NAMA_MKN_MNM, 
         HargaJual = grp.Key.HARGA_JUAL, 
         sumStok = grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM), 
         Tanggal = grp.Key.TGL_TRANSAKSI, 
         Jumlah = grp.Key.HARGA_JUAL * grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM), 
         Total = grp.Sum(grouptotal => grp.Key.HARGA_JUAL * grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM)), 
         Username = grp.Key.USERNAME 
        }); 

我已經得到了一致的foreach投擲（T REC在varlist中） 有沒有簡單的查詢.. ??因爲我迷惑加入3個表... 謝謝你提前

Answer 1

我覺得你的問題是：你 查詢結果是匿名的類型，所以你應該改變這樣的代碼：

var id = (from u in myDb.TBL_TRANSAKSI_MKN_MNMs 
    where u.GL_TRANSAKSI.Value.Date.Equals(dateTimePicker1.Value.Date) 
       join l in myDb.TBL_DETAIL_TRANSAKSIs on u.ID_NOTA equals l.ID_NOTA 
       //into g1 
       join m in myDb.TBL_MKN_MNMs on l.ID_MKN_MNM equals m.ID_MKN_MNM 
       //into g 

       group new {u,l,m} by new {u.TGL_TRANSAKSI, m.NAMA_MKN_MNM, m.HARGA_JUAL, l.ID_MKN_MNM, u.USERNAME}      
       into grp 

       select new MyClass 
       { 
        MakanMinum = grp.Key.NAMA_MKN_MNM, 
        HargaJual = grp.Key.HARGA_JUAL, 
        sumStok = grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM), 
        Tanggal = grp.Key.TGL_TRANSAKSI, 
        Jumlah = grp.Key.HARGA_JUAL * grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM), 
        Total = grp.Sum(grouptotal => grp.Key.HARGA_JUAL * grp.Sum(groupedthing => groupedthing.l.ID_MKN_MNM)), 
        Username = grp.Key.USERNAME 
       }); 


class MyClass 
{ 
    public string MakanMinum {get;set;} 
    ..... 
}