#import <LocalAuthentication/LocalAuthentication.h>

//iOS8.0后才支持指纹识别接口
    if ([UIDevice currentDevice].systemVersion.floatValue < 8.0) {
        return;
    }

- (void)evaluateAuthenticate
{
    //创建LAContext
    LAContext* context = [[LAContext alloc] init];
    NSError* error = nil;
    NSString* result = @"请验证已有指纹";
    
    //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:
                    {
                        //系统取消授权，如其他APP切入
                        break;
                    }
                    case LAErrorUserCancel:
                    {
                        //用户取消验证Touch ID
                        break;
                    }
                    case LAErrorAuthenticationFailed:
                    {
                        //授权失败
                        break;
                    }
                    case LAErrorPasscodeNotSet:
                    {
                        //系统未设置密码
                        break;
                    }
                    case LAErrorTouchIDNotAvailable:
                    {
                        //设备Touch ID不可用，例如未打开
                        break;
                    }
                    case LAErrorTouchIDNotEnrolled:
                    {
                        //设备Touch ID不可用，用户未录入
                        break;
                    }
                    case LAErrorUserFallback:
                    {
                        [[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
        NSLog(@"不支持指纹识别");
        
        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);
    }
}