TouchID

#import "ViewController.h"
#import <LocalAuthentication/LocalAuthentication.h>

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.view.backgroundColor = [UIColor whiteColor];
    
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeSystem];
    btn.frame = CGRectMake(100, 100, 100, 100);
    btn.backgroundColor = [UIColor orangeColor];
    [btn setTitle:@"Touch ID" forState:UIControlStateNormal];
    [btn addTarget:self action:@selector(action) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn];
}


-(void)action
{

    LAContext *laContext =[[LAContext alloc]init];
    NSError *error = nil;
    
    if ([laContext canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]){
        [laContext evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"Touch IDTest" reply:^(BOOL success, NSError * _Nullable error) {
            if (success){
                NSLog(@"success to evaluate");
                
            }else if (error){
                NSLog(@"---failed----%@",error.description);
                switch (error.code) {
                    case LAErrorSystemCancel:
                    {
                        NSLog(@"Authentication was cancelled by the system");
                        //切換到其餘APP，系統取消驗證Touch ID
                        break;
                    }
                    case LAErrorUserCancel:
                    {
                        NSLog(@"Authentication was cancelled by the user");
                        //用戶取消驗證Touch ID
                        break;
                    }
                    case LAErrorUserFallback:
                    {
                        NSLog(@"User selected to enter custom password");
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                            //用戶選擇輸入密碼，切換主線程處理
                        }];
                        break;
                    }
                    default:
                    {
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                            //其餘狀況，切換主線程處理
                        }];
                        break;
                    }
                }
            }
            
        }];
        
    }else{
        
        
        NSLog(@"未調用TouchID=======%@=====",error.description);
        
    }

}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end


typedef NS_ENUM(NSInteger, LAError)
{    //受權失敗
    LAErrorAuthenticationFailed = kLAErrorAuthenticationFailed,    
    //用戶取消Touch ID受權
    LAErrorUserCancel           = kLAErrorUserCancel,    
    //用戶選擇輸入密碼
    LAErrorUserFallback         = kLAErrorUserFallback,    
    //系統取消受權(例如其餘APP切入)
    LAErrorSystemCancel         = kLAErrorSystemCancel,    
    //系統未設置密碼
    LAErrorPasscodeNotSet       = kLAErrorPasscodeNotSet,    //設備Touch ID不可用，例如未打開
    LAErrorTouchIDNotAvailable  = kLAErrorTouchIDNotAvailable,    
    //設備Touch ID不可用，用戶未錄入
    LAErrorTouchIDNotEnrolled   = kLAErrorTouchIDNotEnrolled,
} NS_ENUM_AVAILABLE(10_10, 8_0);

注：輸入錯誤時，alert下發會出現輸入密碼框