null - Is it better to check for null and return or check for non-null and continue?

Question

Given the following basic class:

public class MyClass
{
    private object m_memberVariable;

    public MyClass()
    {
       this.m_memberVariable = new object();
    }
}

Which of the following implementations of the test method is better programming practice?

private void test()
{
   if(this.m_memberVariable == null)
   {
       return;
   }
   System.Diagnostics.Debug.Write(this.m_memberVariable.ToString());
}

Or

private void test()
{
   if(this.m_memberVariable != null)
   {
       System.Diagnostics.Debug.Write(this.m_memberVariable.ToString());
   }
}

In trying to recollect from a professor some 10 years ago, best practice for an if statement is to have the condition that is likely to be true more often than false (the latter). However, recently I have been using a trial of ReSharper, and their suggestion is the former. The m_memberVariable member is initialized at instantiation of the class and will likely be non-null for the life of the class.

Answer 1

我总是尝试检查非 null 并继续 - 然后您只有一个函数退出点，因此退出例程必须仅放置在二进制代码中一次，这会导致较小的结果。但我猜现代编译器无论如何都会优化它，谁知道呢。