iOS 8.0新特性之指纹解锁

iOS 8.0提供了指纹解锁，使用它我们可以轻松进行当前手机用户指纹的确认。

在使用指纹解锁时需要导入头文件

#import <LocalAuthentication/LocalAuthentication.h>

1、初始化LAContext对象

LAContext *context = [LAContext new];

2、对是否支持指纹解锁进行判定

[context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:NULL]

返回值为当前设备是否支持指纹解锁的状态值

3、支持指纹解锁进行指纹解锁的验证

[context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"请输入手势密码" reply:^(BOOL success, NSError * _Nullable error) {
//success 为1 表示密码正确
if (success) {
NSLog(@"手势密码成功");
}else{
// Authentication was not successful, because user failed to provide valid credentials.
//LAErrorAuthenticationFailed  指纹无法识别

// Authentication was canceled by user (e.g. tapped Cancel button).
//LAErrorUserCancel            用户点击取消

// Authentication was canceled, because the user tapped the fallback button (Enter Password).
//LAErrorUserFallback          用户点击输入密码

// Authentication was canceled by system (e.g. another application went to foreground).
//LAErrorSystemCancel          系统取消（如电话）

// Authentication could not start, because passcode is not set on the device.
//LAErrorPasscodeNotSet        用户没有设置指纹

// Authentication could not start, because Touch ID is not available on the device.
//LAErrorTouchIDNotAvailable   不能在此设备上使用指纹
NSLog(@"手势密码失败");
}
}];

完整代码：

//iOS 8.0提供的方法
LAContext *context = [LAContext new];
if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:NULL]) {
NSLog(@"此设备支持指纹");
[context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"请输入手势密码" reply:^(BOOL success, NSError * _Nullable error) {
//success 为1 表示密码正确
if (success) {
NSLog(@"手势密码成功");
}else{
// Authentication was not successful, because user failed to provide valid credentials.
//LAErrorAuthenticationFailed  指纹无法识别

// Authentication was canceled by user (e.g. tapped Cancel button).
//LAErrorUserCancel            用户点击取消

// Authentication was canceled, because the user tapped the fallback button (Enter Password).
//LAErrorUserFallback          用户点击输入密码

// Authentication was canceled by system (e.g. another application went to foreground).
//LAErrorSystemCancel          系统取消（如电话）

// Authentication could not start, because passcode is not set on the device.
//LAErrorPasscodeNotSet        用户没有设置指纹

// Authentication could not start, because Touch ID is not available on the device.
//LAErrorTouchIDNotAvailable   不能在此设备上使用指纹
NSLog(@"手势密码失败");
}
}];
}
else{
NSLog(@"此设备不支持指纹");
}

本人使用模拟器，未能达到理想效果，最好亲自体验。