IOS中UUID存放在不同的地方

前言 

         UUID是什么？UUID其实我们可以理解为应用程序唯一的编号，通俗的可以理解为人的身份证号码一样，是独一无二的。在IOS4.0之前，UUID是对开发者开放的，但是之后为了保护用户的隐私，苹果公司就把这个UUID给禁掉了，但是我们开发人员有时候还是需要这个东东的，所以我们找了一种替代的方法。本文就如何生存替代的 UUID 和 UUID 存放在不同的位置作解释。 

<span style="font-size:18px;">#import <Foundation/Foundation.h>

@interface GetDeviceUUID : NSObject

/**
*  随机生成一个UUID
*
*  @param prefix 生成UUID固定的前缀
*
*  @return 返回一个随机的UUID字符串
*/
+ (NSString *)createCUID:(NSString *)prefix;

/**
*  随机生成一个UUID并保存在 keychain 中
*
*  @param prefix 生成UUID固定的前缀
*
*  @return 返回一个随机的UUID字符串
*/
+ (NSString *)createUUIDInKeychain:(NSString *)prefix;

/**
*  随机生成一个UUID并保存在 keychain 中
*
*  @param prefix 生成UUID固定的前缀
*
*  @return 返回一个随机的UUID字符串
*/
+ (NSString *)createUUIDInNSUserDefault:(NSString *)prefix;

@end
</span>

<span style="font-size:18px;">#import "GetDeviceUUID.h"
#import "KeychainItemWrapper.h"

@implementation GetDeviceUUID

//随机生成一个UUID
+ (NSString *)createCUID:(NSString *)prefix
{
NSString *  result;
CFUUIDRef   uuid;
CFStringRef uuidStr;
uuid = CFUUIDCreate(NULL);
uuidStr = CFUUIDCreateString(NULL, uuid);
result =[NSString stringWithFormat:@"%@-%@", prefix,uuidStr];
CFRelease(uuidStr);
CFRelease(uuid);
return result;
}

//随机生成一个UUID并保存在 keychain 中
+ (NSString *)createUUIDInKeychain:(NSString *)prefix
{
KeychainItemWrapper *wrapper = [[KeychainItemWrapper alloc] initWithIdentifier:@"Account Number" accessGroup:nil];
NSString *keychainUUID = [wrapper objectForKey:(__bridge id)kSecAttrAccount];

if (keychainUUID.length >0) {
return keychainUUID;
}

NSString *  result;
CFUUIDRef   uuid;
CFStringRef uuidStr;
uuid = CFUUIDCreate(NULL);
uuidStr = CFUUIDCreateString(NULL, uuid);
result =[NSString stringWithFormat:@"%@-%@", prefix,uuidStr];
CFRelease(uuidStr);
CFRelease(uuid);

//将生成的UUID保存在 keychain 中
[wrapper setObject:result forKey:(__bridge id)kSecAttrAccount];

return result;
}

//随机生成一个UUID并保存在 NSUserDefaults 中
+ (NSString *)createUUIDInNSUserDefault:(NSString *)prefix
{
NSUserDefaults * userDefaults = [NSUserDefaults standardUserDefaults];
NSString *defaultUUID = [userDefaults stringForKey:@"UUID"];

if (defaultUUID.length >0) {
return defaultUUID;
}

NSString *  result;
CFUUIDRef   uuid;
CFStringRef uuidStr;
uuid = CFUUIDCreate(NULL);
uuidStr = CFUUIDCreateString(NULL, uuid);
result =[NSString stringWithFormat:@"%@-%@", prefix,uuidStr];
CFRelease(uuidStr);
CFRelease(uuid);

[userDefaults setObject:result forKey:@"UUID"];
[userDefaults synchronize];

return result;
}

@end
</span>

温馨提示：在使用 keychain 时需要去下载"KeychainItemWrapper.h/m"文件，并在工程中添加静态库Security.framework。

以下是调用测试的代码片段：

#import "ViewController.h"
#import "KeychainItemWrapper.h"
#import "GetDeviceUUID.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];

UILabel *label1 = [[UILabel alloc] initWithFrame:CGRectMake(5, 60, self.view.frame.size.width-10, 25)];
label1.text = @"测试随机生成UUID,随机可变";
label1.font = [UIFont systemFontOfSize:15.0];
label1.textColor = [UIColor grayColor];
[self.view addSubview:label1];

UILabel *label2 = [[UILabel alloc] initWithFrame:CGRectMake(10, CGRectGetMaxY(label1.frame), self.view.frame.size.width-20, 40)];
label2.lineBreakMode = NSLineBreakByCharWrapping;
label2.numberOfLines = 0;
label2.text = [GetDeviceUUID createCUID:@"Huoshan"];
label2.font = [UIFont systemFontOfSize:15.0];
label2.textColor = [UIColor redColor];
[self.view addSubview:label2];

UILabel *label3 = [[UILabel alloc] initWithFrame:CGRectMake(5, CGRectGetMaxY(label2.frame)+20, self.view.frame.size.width-10, 25)];
label3.text = @"测试生成UUID保存在 keychain 中,固定不变";
label3.font = [UIFont systemFontOfSize:15.0];
label3.textColor = [UIColor grayColor];
[self.view addSubview:label3];

UILabel *label4 = [[UILabel alloc] initWithFrame:CGRectMake(5, CGRectGetMaxY(label3.frame), self.view.frame.size.width-10, 40)];
label4.numberOfLines = 0;
label4.text =  [GetDeviceUUID createUUIDInKeychain:@"Yuancan"];
label4.font = [UIFont systemFontOfSize:15.0];
label4.textColor = [UIColor redColor];
label4.lineBreakMode = NSLineBreakByCharWrapping;
[self.view addSubview:label4];

UILabel *label5 = [[UILabel alloc] initWithFrame:CGRectMake(5, CGRectGetMaxY(label4.frame)+20, self.view.frame.size.width-10, 25)];
label5.text = @"测试生成UUID保存在 NSUserDefault 中,删除应用可变";
label5.font = [UIFont systemFontOfSize:15.0];
label5.textColor = [UIColor grayColor];
[self.view addSubview:label5];

UILabel *label6 = [[UILabel alloc] initWithFrame:CGRectMake(5, CGRectGetMaxY(label5.frame), self.view.frame.size.width-10, 40)];
label6.numberOfLines = 0;
label6.text =  [GetDeviceUUID createUUIDInNSUserDefault:@"Robert"];
label6.font = [UIFont systemFontOfSize:15.0];
label6.textColor = [UIColor redColor];
label6.lineBreakMode = NSLineBreakByCharWrapping;
[self.view addSubview:label6];

}

@end

最后的效果展示：
                                                      


资源下载地址：http://download.csdn.net/detail/u010545480/8788283