char、int、float、double、bool的基本类型转换成对象材耕 NSNumber *charNum = [[NSNumber alloc]initWithChar:'a']; NSNumber *intNum = [[NSNumber alloc]initWithInt:6]; NSNumber *floatNum = [[NSNumber alloc]initWithFloat:0.2]; NSNumber *doubleNum = [[NSNumber alloc]initWithDouble:0.242];
//数组里面的元素是属于对象的。 NSArray *arr = [[NSArray alloc]initWithObjects:charNum,intNum,floatNum,doubleNum, nil];
//两兼距个数进行比较大小 NSComparisonResult result = [intNum compare:intNum1]; if (result == NSOrderedAscending) { NSLog(@'intNum < intNum1'); }else if (result == NSOrderedSame){ NSLog(@'intNum = intNum1'); }else{ NSLog(@'intNum > intNum1'); }
//对象转换成基本类型char、int、float、double char c = [charNum charValue]; int i = [intNum intValue]; float f = [floatNum floatValue]; double d = [doubleNum doubleValue]; NSLog(@'%c,%d,%f,%lf',c,i,f,d);