Beginners C#query

[doodab]

Of course one reason you have to put return values into a variable rather than use them directly is that people writing the methods often return null when they should have thrown an exception so you need to check the value before you use it. This gets on my tits.

[Scrag Meister]

Thanks so much for the replies.

Minestrone, sorry hasty on the neg, I think the some total of your contributions was worth a +ve, even if bits of your code didn't do what mine did. . Will correct in due course.

P.S. There is a LOT more data manipulation code in the loop I just cleared it out to make clear the bit I was asking about. Performance is important but not THAT important in this situation.

Thank you all again.

[RasputinDude]

Human readable code over compiler friendly code every day of the week.

Totally agree, I *hate* it when people try to something clever in a couple of lines of code which then take ages to debug.

I wouldn't use this construct at all :

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

But

++i

or

if (1==i)

I think these are easily human readable.

Not that I would use a variable called "i" though.

[Scrag Meister]

Totally agree, I *hate* it when people try to something clever in a couple of lines of code which then take ages to debug.

I wouldn't use this construct at all :

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

But

++i

or

if (1==i)

I think these are easily human readable.

Not that I would use a variable called "i" though.

Old habits die hard, always use i or j etc as simple loop counters.

[VectraMan]

I thought I'd see what VC10 would do, and in debug so no optimisations:

    ++i;
3D60FBD0  mov         edx,dword ptr [i]  
3D60FBD3  add         edx,1  
3D60FBD6  mov         dword ptr [i],edx  
    i++;
3D60FBD9  mov         eax,dword ptr [i]  
3D60FBDC  add         eax,1  
3D60FBDF  mov         dword ptr [i],eax  
    i=i+1;
3D60FBE2  mov         ecx,dword ptr [i]  
3D60FBE5  add         ecx,1  
3D60FBE8  mov         dword ptr [i],ecx

All three produce exactly the same code. So on that basis, we should probably all be writing i=i+1 for clarity instead of ++i or i++.

[RasputinDude]

we should probably all be writing i=i+1 for clarity instead of ++i or i++.

Wash your mouth out.

It should be

i+=1

and I'll brook no argument.

[Jaws]

Old habits die hard, always use i or j etc as simple loop counters.

Likewise, in my mind it is far easier to read and the better approach for loop of that nature.

I think "while( (data = sr.ReadLine()) != null )" is fine too, it's a common pattern and therefore easy enough to read.

[Scrag Meister]

Likewise, in my mind it is far easier to read and the better approach for loop of that nature.

I think "while( (data = sr.ReadLine()) != null )" is fine too, it's a common pattern and therefore easy enough to read.

So with that in mind I could do this too? i.e. Assign to my data string all within the same statement.

while ( sr.Peek() > -1) {
Console.WriteLine(iRows++ + " - " + (data = sr.ReadLine()));

// Process the string "data"

}

At this rate I should be able to squeeze the whole process into 3 lines LOL. Not really but this is very interesting to me. Thanks.

[VectraMan]

Don't forget to use the comma operator:

Console.WriteLine(iRows++ + " - " + (data = sr.ReadLine(), somethingElse = thing.SomethingElse(), iRows<<=2, someExtremelyLargeAndSlowOperation() ));

Chuck in some lambda functions (can C# do that?) and you can write an entire program in one statement.

[RasputinDude]

Starting to look like an entry for the IOCCC (The International Obfuscated C Code Contest)