如何在此代码上实现快速枚举

Question

I want to implement fast enumeration on this code, please help me.

int xx;
int b=0;

for (xx=0 ; xx<(distancearray.count); xx++) {
    if ([NSNull null]!=[distancearray objectAtIndex:xx]&& 0 !=[[[distancearray objectAtIndex:xx] description] intValue] ) {
        b++;
        latitudeLabel.text=[NSString stringWithFormat:@" %d",b*100];
    }

}

Answer 1

Try this :

for( id object in distancearray){
    if ([NSNull null]!=object && 0 !=[[object description] intValue] ) {
        b++;
        latitudeLabel.text=[NSString stringWithFormat:@" %d",b*100];
    }
}

Answer 2

For simplicity sake:

for( id object in distancearray){
    if (object && [[object description] intValue] != 0) {
        b++;
        latitudeLabel.text=[NSString stringWithFormat:@" %d",b*100];
    }
}

To know about iterating an array: How do I iterate over an NSArray?