#import <LocalAuthentication/LocalAuthentication.h>

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

- (void)evaluatePolicy:(LAPolicy)policy  localizedReason:(NSString *)localizedReason     reply:(void(^)(BOOL success, NSError * __nullable error))reply;

 //創建LAContext LAContext *context = [LAContext new];  //這個屬性是設置指紋輸入失敗之后的彈出框的選項 context.localizedFallbackTitle = @"沒有忘記密碼";

NSError *error = nil; if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {  NSLog(@"支持指紋識別");  [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"指紋解鎖" reply:^(BOOL success, NSError * _Nullable error) {   if (success) {    NSLog(@"驗證成功 刷新主界面");   }else{    NSLog(@"%@",error.localizedDescription);    switch (error.code) {     case LAErrorSystemCancel:     {      NSLog(@"系統取消授權，如其他APP切入");      break;     }     case LAErrorUserCancel:     {      NSLog(@"用戶取消驗證Touch ID");      break;     }     case LAErrorAuthenticationFailed:     {      NSLog(@"授權失敗");      break;     }     case LAErrorPasscodeNotSet:     {      NSLog(@"系統未設置密碼");      break;     }     case LAErrorTouchIDNotAvailable:     {      NSLog(@"設備Touch ID不可用，例如未打開");      break;     }     case LAErrorTouchIDNotEnrolled:     {      NSLog(@"設備Touch ID不可用，用戶未錄入");      break;     }     case LAErrorUserFallback:     {      [[NSOperationQueue mainQueue] addOperationWithBlock:^{       NSLog(@"用戶選擇輸入密碼，切換主線程處理");      }];      break;     }     default:     {      [[NSOperationQueue mainQueue] addOperationWithBlock:^{       NSLog(@"其他情況，切換主線程處理");      }];      break;     }    }   }  }]; }else{  NSLog(@"不支持指紋識別");  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); }