Syntax help - Variable as object name [duplicate]

问题:

Possible Duplicate:
create multiple variables based on an int count
Objective C Equivalent of PHP's “Variable Variables”

How would I create and reference an object using a variable as it\'s name?

Example -

    for (int i=1; i<7; i++) {
       CGRect (\"myRectNum & i\") = myImageView.bounds; 
    }

 (\"myRectNum & 5\").height  etc ..

回答1:

There isn\'t anything like this in the Objective-C language, and in general it\'s not going to be a very practical way of referring to data (what if you typo a string? the compiler won\'t be able to catch it). I won\'t get into second-guessing what you actually want to do (that would depend on the goal of this part of your application), but you can use an NSMutableDictionary to get a similar effect:

NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
for (int i = 0; i < 7; i++)
{
    NSString *key = [NSString stringWithFormat:@\"myRectNum & %d\", i];
    NSValue *value = [NSValue valueWithCGRect:myImageView.bounds];
    [dict setObject:value forKey:key];
}

Then to fetch the values back out again:

NSValue *value = [dict objectForKey:@\"myRectNum & 5\"];
CGRect bounds = [value CGRectValue];
NSLog(@\"height = %f\", bounds.size.height);