ios TouchID

1.引入指纹解锁必须的头文件

#import 

2.了解TouchID最主要的两个方法
这个方法是判断设备是否支持TouchID的。

- (BOOL)canEvaluatePolicy:(LAPolicy)policy error:(NSError* __autoreleasing *)error __attribute__((swift_error(none)));

这个是用来验证TouchID的，会有弹出框出来。

- (void)evaluatePolicy:(LAPolicy)policy localizedReason:(NSString*)localizedReason reply:(void(^)(BOOLsuccess,NSError* __nullableerror))reply;

3.首先,新建LAContext对象

//创建LAContextLAContext *context = [LAContextnew];
//这个属性是设置指纹输入失败之后的弹出框的选项context.localizedFallbackTitle = @"没有忘记密码";

4.然后实现回调方法，包括成功以及失败的

NSError *error = nil;
    if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {
        NSLog(@"支持指纹识别");
        [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"请按home键指纹解锁" reply:^(BOOL success, NSError * _Nullable error) {
            if (success) {
                NSLog(@"验证成功 刷新主界面");
            }else{
                NSLog(@"%@",error.localizedDescription);
                switch (error.code) {
                    case LAErrorSystemCancel:
                    {
                        NSLog(@"系统取消授权，如其他APP切入");
                        break;
                    }
                    case LAErrorUserCancel:
                    {
                        NSLog(@"用户取消验证Touch ID");
                        break;
                    }
                    case LAErrorAuthenticationFailed:
                    {
                        NSLog(@"授权失败");
                        break;
                    }
                    case LAErrorPasscodeNotSet:
                    {
                        NSLog(@"系统未设置密码");
                        break;
                    }
                    case LAErrorTouchIDNotAvailable:
                    {
                        NSLog(@"设备Touch ID不可用，例如未打开");
                        break;
                    }
                    case LAErrorTouchIDNotEnrolled:
                    {
                        NSLog(@"设备Touch ID不可用，用户未录入");
                        break;
                    }
                    case LAErrorUserFallback:
                    {
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                            NSLog(@"用户选择输入密码，切换主线程处理");
                        }];
                        break;
                    }
                    default:
                    {
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                            NSLog(@"其他情况，切换主线程处理");
                        }];
                        break;
                    }
                }
            }
        }];
    }else{
        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);
    }