取以下函数:

DataTable go() {
    return someTableAdapter.getSomeData();
}

当我在这个函数中设置断点时,是否有可能检查返回值?Go()直接耦合到.aspx页面中的数据网格。

检查返回数据表的唯一方法是使用临时变量。然而,这有点不方便。没有别的办法了吗?


当前回答

接受的答案在Visual Studio 2015中不能正常工作,但是通过在方法的最后一行上放置断点并按F10,它将把返回值的所有表达式放入locals窗口。

其他回答

是的,通过切换到VB.NET。P)你刚才说了“Visual Studio”。,)

在我的记忆中(从Visual Basic到VB.NET的所有版本),您可以简单地查询函数名。它像一个局部变量一样“起作用”,在函数开始时隐式声明,它的当前值也被用作函数通过非返回语句退出时的返回值(即Exit function或只是falling through),当然,当使用return语句时。

它还被设置为return语句的表达式。就像局部变量一样,它的值可以在函数内部的任何执行点检查(包括在return语句执行之后)。c#没有,也应该有。

That little VB.NET feature (plus the Exit Function statement which it enables - another feature C# doesn't have and should) is very useful in a form of defensive programming I practice where I always initialize the function name to the failure/default value as the first statement. Then, at any failure point (which normally occurs much more often than success points), I can simply call the Exit Function statement (i.e. without having to duplicate the failure / default expression or even a constant/variable name).

进入“工具→选项”、“IntelliTrace”菜单,修改设置,收集事件和呼叫信息。

您可以返回到前面的调用事件(Ctrl + Shift + F11),并在autos窗口中看到方法调用返回的临时值作为方法名的子值。

这并没有显示您所在方法的返回值。它只显示当前方法中调用的最后一个方法的返回值。

所以,对于

DataTable go(){return someTableAdapter.getSomeData();}

因为它会显示someTableAdapter.getSomeData()的返回值。

但不是为了:

int go(){return 100 * 99;}

我认为您可以通过查看寄存器窗口(调试/ Windows /寄存器)中的RAX寄存器来确定这一点。退出函数(SHIFT + F11)后,检查RAX寄存器。我不知道事实,但你可以检查一个寄存器(在。net时代之前)并看到那里的返回值。它甚至可能是RAX和RBX的组合,等等。

我知道的唯一方法是在返回行上放置一个断点,然后调用Quick Watch窗口并输入返回的表达式:

someTableAdapter.getSomeData();

但这只有在调用不改变任何对象的状态时才有效(因为当您恢复执行时,将会对同一方法进行第二次调用)。

根据微软的说法,没有办法用托管代码可靠地实现这一点。这是他们意识到并正在努力解决的问题:

For those out there who have experience debugging native C++ or VB6 code, you may have used a feature where function return values are provided for you in the Autos window. Unfortunately, this functionality does not exist for managed code. While you can work around this issue by assigning the return values to a local variable, this is not as convenient because it requires modifying your code. In managed code, it’s a lot trickier to determine what the return value of a function you’ve stepped over. We realized that we couldn’t do the right thing consistently here and so we removed the feature rather than give you incorrect results in the debugger. However, we want to bring this back for you and our CLR and Debugger teams are looking at a number potential solutions to this problem. Unfortunately this is will not be part of Visual Studio 11.

https://connect.microsoft.com/VisualStudio/feedback/details/597933/add-a-return-pseudo-variable-to-the-visual-studio-debugger-for-net-code