iOS实现生物识别

1. info.plist中添加权限申请

<key>NSFaceIDUsageDescription</key>
<string>APP would like to use Face ID</string>
<key>NSBiometricUsageDescription</key>
<string>APP would like to use Touch ID</string>

2. 添加库

Build Phases → Link Binary With Libraries → LocalAuthentication.framework

3. 实现代码

#import <LocalAuthentication/LocalAuthentication.h>

// 检查是否支持认证
-(BOOL) isSupportBiometricCheck {
    LAContext *context = [[LAContext alloc] init];
    NSError *error = nil;
    
    // 检查设备是否支持生物识别认证
    if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthentication error:&error]) {
        return true;
    } else {
        return false;
    }
}

// 认证
// title：标题 eg.生物识别登录
// subTitle：副标题 eg.使用生物识别凭证登录
// negativeText：取消文本 eg.取消
- (void)biometricCheck:(CallSN)cbSn title:(NSString *)title
              subTitle:(NSString *)subTitle
        negativeButton:(NSString *)negativeText {
    LAContext *context = [[LAContext alloc] init];
    
    NSString *localizedReason = [NSString stringWithFormat:@"%@\\n%@", title, subTitle];
    
    [context evaluatePolicy:LAPolicyDeviceOwnerAuthentication
            localizedReason:localizedReason
                      reply:^(BOOL success, NSError * _Nullable error) {
        dispatch_async(dispatch_get_main_queue(), ^{
            if (success) {
                NSLog(@"认证成功");
            } else {
                NSLog(@"认证失败，原因:%@", error.description);
            }
        });
    }];
}

目前来看LAPolicyDeviceOwnerAuthentication优于LAPolicyDeviceOwnerAuthenticationWithBiometrics，因为LAPolicyDeviceOwnerAuthenticationWithBiometrics在验证失败时，需要重新输入一次锁屏密码或者调用LAPolicyDeviceOwnerAuthentication输入密码才可以再次被正常调用。否则直接返回生物特征已锁定，而引起认证失败。