無效的匿名類型成員聲明中加入兩個DataTable

Question

我嘗試做以下連接：

var collection = from t1 in dt1.AsEnumerable() 
       join t2 in dt2.AsEnumerable() 
       on new { 
        t1.["main_code"], 
        t1["year"]} 
        equals new { 
         t2["dep_code"], 
         t2["dep_year"] } 
         select new { 
          emp_name = t1["name"], 
          bonus_desc = t1["bonus_desc"], 
          dep_name = t2["dep_name"] }; 

，但我面對下面的生成錯誤！

無效的匿名類型成員聲明

Answer 1

匿名類型的名稱屬性join：

var collection = from t1 in dt1.AsEnumerable() 
       join t2 in dt2.AsEnumerable() 
       on new { PropertyA= t1["main_code"], PropertyB=t1["year"]} equals new { PropertyA=t2["dep_code"], PropertyB=t2["dep_year"] } 
       select new { emp_name = t1["name"], bonus_desc = t1["bonus_desc"],dep_name = t2["dep_name"] }; 

Answer 2

你需要明確地命名的屬性，例如：

var collection = 
    from t1 in dt1.AsEnumerable() 
    join t2 in dt2.AsEnumerable() 
    on new { code = t1["main_code"], year = t1["year"] } equals 
     new { code = t2["dep_code"], year = t2["dep_year"] } 
    select new { emp_name = t1["name"], bonus_desc = t1["bonus_desc"] /* ... */}; 

Answer 3

使用：

var collection = from t1 in dt1.AsEnumerable() 
       join t2 in dt2.AsEnumerable() 
       on new { field1 = t1.["main_code"], field2 = t1["year"]} equals new { field1 = t2["dep_code"], field2 = t2["dep_year"] } 
       select new { emp_name = t1["name"], bonus_desc = t1["bonus_desc"],dep_name = t2["dep_name"] };