在这个ObjectSet <T> .SelectValue的例子中,"它"来自哪里？

Question

productQuery1.SelectValue<Int32>("it.ProductID");

我怎么知道"它"在这里意味着什么？

来自MSDN docs的完整示例

using (AdventureWorksEntities context =
    new AdventureWorksEntities())
{
    string queryString =
        @"SELECT VALUE product FROM 
            AdventureWorksEntities.Products AS product";

    ObjectQuery<Product> productQuery1 =
        new ObjectQuery<Product>(queryString,
            context, MergeOption.NoTracking);

    ObjectQuery<Int32> productQuery2 =
        productQuery1.SelectValue<Int32>("it.ProductID");

    foreach (Int32 result in productQuery2)
    {
        Console.WriteLine("{0}", result);
    }
}

Answer 1

它更像是this.

它是查询构建器方法中的约定.

在查询构建器方法中,使用别名引用当前的ObjectQuery命令.默认情况下,字符串"it"是表示当前命令的别名...