＆QUOT;与语句体一个lambda前pression不能转换为前pression树＆QUOT; [英] "A lambda expression with a statement body cannot be converted to an expression tree"

问题描述

在使用的EntityFramework 后，我得到的错误的语句体一个lambda前pression不能转换为前pression树，试图编译以下code时：

In using the EntityFramework, I get the error "A lambda expression with a statement body cannot be converted to an expression tree" when trying to compile the following code:

Obj[] myArray = objects.Select(o =>
{
    var someLocalVar = o.someVar;

    return new Obj() { 
    Var1 = someLocalVar,
    Var2 = o.var2 };
}).ToArray();

我不知道是什么错误意味着最重要的是如何解决它。任何帮助吗？谢谢

I don't know what the error means and most of all how to fix it. Any help? Thanks

推荐答案

是对象 A LINQ到SQL数据库环境？在这种情况下，你只能使用简单的前pressions到=>运算符的右侧。原因是，这些前pressions不被执行，而是被转换为SQL要对数据库执行。
试试这个

Is objects a Linq-To-SQL database context? In which case, you can only use simple expressions to the right of the => operator. The reason is, these expressions are not executed, but are converted to SQL to be executed against the database. Try this

Arr[] myArray = objects.Select(o => new Obj() { 
    Var1 = o.someVar,
    Var2 = o.var2 
}).ToArray();

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