NSValue&NSNumber
void testForNSValue(void)
{
int i=10;
// NSLog(@"encode(int)=%s",@encode(int));
// NSLog(@"encode(float)=%s",@encode(float));
// NSLog(@"encode(struct student)=%s",@encode(struct student));
NSValue* value =[[NSValue alloc]initWithBytes:&i objCType:@encode(int) ];
int ret;
[value getValue:&ret];
NSLog(@"ret=%i",ret);
struct s stt={88,99};
NSValue* value2 =[[ NSValue alloc]initWithBytes:&stt objCType:@encode(struct s)];
struct s newStt;
[value2 getValue:&newStt];
NSLog(@"newStt.a=%i, newStt.b=%i",newStt.a,newStt.b);
NSLog(@"objCType is %s", [value2 objCType]);
// @encode(struct s) == [value2 objCType]
int *p=&i;
NSLog(@"p=%p",p);
NSValue* v3 = [[ NSValue alloc]initWithBytes:&p objCType:@encode(int *)];
int *q;
[v3 getValue:&q];
NSLog(@"q=%p",q);
}
void testNSNumber(void)
{
//对4字节有符号整型
NSNumber *obj1 = [ NSNumber numberWithInt:123];
NSLog(@"obj1 is %i",[obj1 intValue]);
//对8字节有符号整型
NSNumber *obj2 = [ NSNumber numberWithInteger:88888888];
NSLog(@"obj2 is %li", [obj2 integerValue]);
//对4字节无符号整型
NSNumber * obj3 = [ NSNumber numberWithUnsignedInt:345];
NSLog(@"obj3 is %u", [obj3 unsignedIntValue]);
//对8字节无符号整型
NSNumber* obj4 = [ NSNumber numberWithUnsignedInteger:99999999];
NSLog(@"obj4 is %lu", [obj4 unsignedIntegerValue]);
//其它的基本数据类型的封装方法
// NSNumber numberWithUnsignedChar:<#(unsigned char)#>
// obj4 unsignedCharValue
// NSNumber numberWithShort:<#(short)#>
// obj4 shortValue
// NSNumber numberWithUnsignedLongLong:<#(unsigned long long)#>
// obj4 unsignedLongLongValue
NSNumber* obj5 = [ NSNumber numberWithBool:YES];
NSLog(@"obj5 is %i",[obj5 boolValue]);
int a;
NSNumber * obj6 = [NSNumber numberWithUnsignedLong:(unsigned long)&a];
int * add = (int *)[obj6 unsignedLongValue];
}