While Syntax

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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

C#

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

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

C#

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

Posted 7-Sep-10 14:47pm

Adam R Harris

Updated 7-Sep-10 22:48pm

Dalek Dave

v3

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Chris Maunder 7-Sep-10 22:48pm

You can. You can also write code that's easily read by all levels of programmers that may need to touch your code. I prefer clarity to cleverness.

Dalek Dave 8-Sep-10 4:48am

Edited for Grammar.

Adam R Harris 8-Sep-10 10:46am

Have to agree with you Chris.... just nice to know. However I’m not entirely sure that you sacrifice clarity with this particular brand of cleverness, but as a whole I have to agree that clarity is much more important than cleverness.

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Not Active · Accepted Answer · 2010-09-07T15:00:00

Solution 1

Close, missing a set of parentheses

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

Posted 7-Sep-10 15:00pm

Not Active

Comments

Adam R Harris 7-Sep-10 21:05pm

Figures .... all this time .... time to update the code :)

Dalek Dave 8-Sep-10 4:48am

Well Spotted.