#import <LocalAuthentication/LocalAuthentication.h>

//iOS8.0后才支持指紋識別接口  if ([UIDevice currentDevice].systemVersion.floatValue < 8.0) {    return;  }

- (void)evaluateAuthenticate{  //創建LAContext  LAContext* context = [[LAContext alloc] init];  NSError* error = nil;  NSString* result = @"請驗證已有指紋";  //首先使用canEvaluatePolicy 判斷設備支持狀態  if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {    //支持指紋驗證    [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:result reply:^(BOOL success, NSError *error) {      if (success) {        //驗證成功，主線程處理UI      }      else      {        NSLog(@"%@",error.localizedDescription);        switch (error.code) {          case LAErrorSystemCancel:          {            //系統取消授權，如其他APP切入            break;          }          case LAErrorUserCancel:          {            //用戶取消驗證Touch ID            break;          }          case LAErrorAuthenticationFailed:          {            //授權失敗            break;          }          case LAErrorPasscodeNotSet:          {            //系統未設置密碼            break;          }          case LAErrorTouchIDNotAvailable:          {            //設備Touch ID不可用，例如未打開            break;          }          case LAErrorTouchIDNotEnrolled:          {            //設備Touch ID不可用，用戶未錄入            break;          }          case LAErrorUserFallback:          {            [[NSOperationQueue mainQueue] addOperationWithBlock:^{              //用戶選擇輸入密碼，切換主線程處理            }];            break;          }          default:          {            [[NSOperationQueue mainQueue] addOperationWithBlock:^{              //其他情況，切換主線程處理            }];            break;          }        }      }    }];  }  else  {    //不支持指紋識別，LOG出錯誤詳情    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);  }}