Question

我计划加入2个表，并获得语言列的不同值。我应该如何在Linq实现这一目标？我尝试添加'组'但没有运气。此外，我想与r不同的语言值一起选择s值。

我的代码：

 public ActionResult QuestionLink(int Survey_ID)
        {
            var query = from r in db.SURV_Question_Ext_Model
                        join s in db.SURV_Question_Model
                        on r.Qext_Question_ID equals s.Question_ID
                        where s.Question_Survey_ID == Survey_ID
                        group r.language << this is not work **
                        select r;

            return PartialView(query.ToList());
        }

Answer 1

这就是MoreLinq中<button onclick="getLocation()">Try It</button> <p id="demo"></p> <script> var x = document.getElementById("demo"); function getLocation() { if (navigator.geolocation) { navigator.geolocation.getCurrentPosition(showPosition); } else { x.innerHTML = "Geolocation is not supported by this browser."; } } function showPosition(position) { x.innerHTML = "Latitude: " + position.coords.latitude + "<br>Longitude: " + position.coords.longitude; } </script>所称的内容。但是，如果该方法适用于<script type="text/javascript"> var adjustementType = { -1:'Rate Decrease', 1: 'Rate Increase' }; </script>，那么您就无法在EF查询中使用它。但是你可以使用相同的方法：

DistinctBy

但我想知道这是否真的是你想要的。结果取决于数据库碰巧返回的语言顺序。我认为您应该为特定语言添加谓词并删除分组：

IEnumerable

Answer 2

你可以这样做：

var query = from r in db.SURV_Question_Ext_Model
                        join s in db.SURV_Question_Model
                        on r.Qext_Question_ID equals s.Question_ID
                        where s.Question_Survey_ID == Survey_ID
                        group new {r, s} by r.language into rg
                        select rg.Key;

Linq Group by / Distinct with Join table

2 个答案: