iOS开发技巧：使用Objective-C创建UUID的代码

- (NSString *)createUUID
{
// Create universally unique identifier (object)
CFUUIDRef uuidObject = CFUUIDCreate(kCFAllocatorDefault);

// Get the string representation of CFUUID object.
NSString *uuidStr = [(NSString *)CFUUIDCreateString(kCFAllocatorDefault, uuidObject) autorelease];

// If needed, here is how to get a representation in bytes, returned as a structure
// typedef struct {
// UInt8 byte0;
// UInt8 byte1;
// ...
// UInt8 byte15;
// } CFUUIDBytes;
CFUUIDBytes bytes = CFUUIDGetUUIDBytes(uuidObject);

CFRelease(uuidObject);

return uuidStr;
}