虽然语法 [英] While Syntax

问题描述

好吧，所以我知道这听起来有些奇怪，但是有人告诉我您可以分配一个值并在while子句中检查null，即

Ok, so I know it sounds a little strange but someone was telling me that you can assign a value AND check for null in a while clause i.e

string line;
StreamReader sr = new StreamReader("some file");
while(line = sr.ReadLine() != null)
{
    // do something with line
}

看起来或听起来不正确，但这是一个不错的捷径:

Doesn''t look or sound right, but it would be a nice short cut over:

string line;
StreamReader sr = new StreamReader("some file");
line = sr.ReadLine();
while(line != null)
{
    // do something with line
    line = sr.ReadLine();
}

推荐答案

关闭，缺少一组括号

Close, missing a set of parentheses

while( (line = sr.ReadLine()) != null)

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