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Re: if statement
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Re: if statement


  • Subject: Re: if statement
  • From: Andy Lee <email@hidden>
  • Date: Tue, 27 May 2008 17:35:20 -0400

On May 27, 2008, at 5:26 PM, Nick Zitzmann wrote:
On May 27, 2008, at 3:24 PM, Nathan wrote:

- (IBAction)operators:(id)sender {
	OB=[operatorBar floatValue];
	if (OB=1) {
		[operator setFloatValue: 4];
	}
	if (OB=2) {
		[operator setFloatValue: 5];
	}
}

So you would expect that if operatorBar = 1, then OB will = 1, and operator will = 4. I know the first part is ok due to testing, but what happens when I run the program is that it acts like the if's don't exist, so upon using operators method operator will equal 5 no matter what. What's wrong here?


In C, a single = is an assignment; a double == is a check for equality.

Yup, and an assignment expression (like OB=2) evaluates to the value that was assigned (in this caes, 2).


And conditionals in C treat 0 as false, and treat non-zero as true, which is why both of your ifs always evaluate to true.

--Andy

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References: 
 >if statement (From: Nathan <email@hidden>)
 >Re: if statement (From: Nick Zitzmann <email@hidden>)

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