:添加LocalAuthentication.framework框架

:实现过程

#import "ViewController.h"

#import <LocalAuthentication/LAContext.h>

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    LAContext *myContext = [[LAContext alloc]init];

    myContext.localizedFallbackTitle = @"忘记密码";

    NSError *error = nil;

    NSString *myLocalizedReasonString = @"请输入指纹";

    if ([myContext canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {

        [myContext evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics

                  localizedReason:myLocalizedReasonString

                            reply:^(BOOL success, NSError *error) {

                                if (success) {

                                    NSLog(@"success");

                                } else {

                                    // User did not authenticate successfully, look at error and take appropriate action

                                 NSLog(@"did not authenticate successfully");

                                }

                            }];

    } else {

        // Could not evaluate policy; look at authError and present an appropriate message to user

       NSLog(@"Could not evaluate policy");

    }

}