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C# 如何找到从<;返回的第一个元素&燃气轮机;SQLite返回的列表类型?_C#_Sqlite_Xamarin - Fatal编程技术网

C# 如何找到从<;返回的第一个元素&燃气轮机;SQLite返回的列表类型?

C# 如何找到从<;返回的第一个元素&燃气轮机;SQLite返回的列表类型?,c#,sqlite,xamarin,C#,Sqlite,Xamarin,我正在审查以下代码: var phrases = db2 .Query<Phrase>("SELECT C.Id As CategoryId" + " FROM Category AS C" + " JOIN Phrase AS P ON C.Id = P.CategoryId"); var-

我正在审查以下代码:

           var phrases = db2
                .Query<Phrase>("SELECT C.Id As CategoryId" +
                              " FROM Category AS C" +
                              " JOIN Phrase AS P ON C.Id =          P.CategoryId");
var-phrases=db2
.Query(“选择C.Id作为类别Id”+
“从类别C开始”+
“在C.Id=P.CategoryId上连接短语作为P”);
短语的类型为
列表

现在我想找到列表的第一个元素。但在我的IDE中,当我将鼠标悬停在“短语”上时,我在另一行看到的是获取.count.add.addRange.find和类似项的选项

有人能解释一下如何获取第一个元素吗?

添加
FirstOrDefault()

var-phrases=db2
.Query(@“选择C.Id作为类别Id
从C类开始
将短语作为P连接到C.Id=P.CategoryId“.FirstOrDefault();
添加
FirstOrDefault()

var-phrases=db2
.Query(@“选择C.Id作为类别Id
从C类开始
将短语作为P连接到C.Id=P.CategoryId“.FirstOrDefault();
var phrases = db2
                .Query<Phrase>(@"SELECT C.Id As CategoryId
                               FROM Category AS C
                               JOIN Phrase AS P ON C.Id = P.CategoryId").FirstOrDefault();