ios的touch ID 验证开发

• (void)authenticateUser
  {
  //初始化上下文对象
  LAContext* context = [[LAContext alloc] init];
  //错误对象
  NSError* error = nil;
  NSString* result = @”Authentication is needed to access your notes.”;

  //首先使用canEvaluatePolicy 判断设备支持状态
  if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {
  //支持指纹验证
  [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:result reply:^(BOOL success, NSError *error) {
  if (success) {
  //验证成功，主线程处理UI˜

      }
      else
      {
          NSLog(@"%@",error.localizedDescription);
          switch (error.code) {
              case LAErrorSystemCancel:
              {
                  NSLog(@"Authentication was cancelled by the system");
                  //切换到其他APP，系统取消验证Touch ID
                  break;
              }
              case LAErrorUserCancel:
              {
                  NSLog(@"Authentication was cancelled by the user");
                  //用户取消验证Touch ID
                  break;
              }
              case LAErrorUserFallback:
              {
                  NSLog(@"User selected to enter custom password");
                  [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                      //用户选择输入密码，切换主线程处理
                  }];
                  break;
              }
              default:
              {
                  [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                      //其他情况，切换主线程处理
                  }];
                  break;
              }
          }
      }
  }];
  

  }
  else
  {
  //不支持指纹识别，LOG出错误详情

  switch (error.code) {
      case LAErrorTouchIDNotEnrolled:
      {
          NSLog(@"TouchID is not enrolled");
          break;
      }
      case LAErrorPasscodeNotSet:
      {
          NSLog(@"A passcode has not been set");
          break;
      }
      default:
      {
          NSLog(@"TouchID not available");
          break;
      }
  }
  
  NSLog(@"%@",error.localizedDescription);
  [self showPasswordAlert];// 验证密码的方法，自己定义与实现
  

  }
  }