iOS开发：使用苹果自带框架实现二维码和条形码扫描

扫描二维码和条形码，用的是AVFoundation，判断如果是URL就打开web页面。

预览

思路

• AVFoundation框架很强大，调摄像头各种硬件
• 判断URL用正则表达式

主要代码

////  CaptureViewController.m//  ScanCode////  Created by yxhe on 16/6/2.//  Copyright © 2016年 yxhe. All rights reserved.//#import <AVFoundation/AVFoundation.h>#import "CaptureViewController.h"#import "BrowserViewController.h"const char *kScanCodeQueueName = "ScanCodeQueue"; //the new process queue indentifier@interface CaptureViewController ()<AVCaptureMetadataOutputObjectsDelegate>{    AVCaptureSession *session; //the session of captrue    BOOL isLightOpen;}@property (nonatomic, strong) UIView *cameraView; //the camera frame view@property (nonatomic, strong) UIButton *openLightBtn; //open the light@end@implementation CaptureViewController- (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view.        //add the cameara view    _cameraView = [[UIView alloc] initWithFrame:CGRectMake(0, 100, self.view.frame.size.width, self.view.frame.size.width)];    _cameraView.backgroundColor = [UIColor lightGrayColor];    [self.view addSubview:_cameraView];        //add a button to switch light    isLightOpen = NO;    UIButton *lightButton = [UIButton buttonWithType:UIButtonTypeCustom];    lightButton.frame = CGRectMake(self.view.frame.size.width/2 - 50, 500, 100, 50);    [lightButton setTitle:@"open_light" forState:UIControlStateNormal];    [lightButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];    [lightButton setTitleColor:[UIColor greenColor] forState:UIControlEventTouchDown];    [lightButton addTarget: self action:@selector(switchLight) forControlEvents:UIControlEventTouchUpInside];    [self.view addSubview:lightButton];                //start capture    [self initCapture];    [session startRunning];    }- (void)loadView{    [super loadView];//    [self initCapture];}- (void)viewDidAppear:(BOOL)animated{    [super viewDidAppear:animated];//    [self initCapture];}- (void)switchLight{    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];    //toggle the light    isLightOpen = !isLightOpen;    //turn on or off the light    if([device hasTorch])    {        [device lockForConfiguration:nil];                if(isLightOpen)            [device setTorchMode:AVCaptureTorchModeOn];        else            [device setTorchMode:AVCaptureTorchModeOff];                [device unlockForConfiguration];    }        }- (void)initCapture{    //get the camera device    AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];        //create the session    session = [[AVCaptureSession alloc]init];        //create input    NSError *error;    AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];    if(!input)    {        NSLog(@"%@", [error localizedDescription]);        return;    }    [session addInput:input];        //create output    AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];    [session addOutput:output];        //make it run at a new process    dispatch_queue_t dispatchQueue;    dispatchQueue = dispatch_queue_create(kScanCodeQueueName, NULL);    [output setMetadataObjectsDelegate:self queue:dispatchQueue];            //set the sampling rate    [session setSessionPreset:AVCaptureSessionPresetHigh];        //set the code type ,ex:QR and bar code    if([output.availableMetadataObjectTypes containsObject:AVMetadataObjectTypeQRCode])        [output setMetadataObjectTypes:[NSArray arrayWithObjects:AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code, nil]];        //add the camera layer    AVCaptureVideoPreviewLayer *captureLayer = [AVCaptureVideoPreviewLayer layerWithSession:session];    captureLayer.videoGravity=AVLayerVideoGravityResizeAspectFill;    captureLayer.frame=self.cameraView.layer.bounds;    [self.cameraView.layer insertSublayer:captureLayer atIndex:0]; //or use the addsublayer//    [self.cameraView.layer addSublayer:captureLayer];    }#pragma mark - capture delegate-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{    if (metadataObjects && metadataObjects.count>0)    {        //stop the capture        [session stopRunning];        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];        //do sth to handle the capture result        [self performSelectorOnMainThread:@selector(handleResult:) withObject:metadataObject waitUntilDone:NO];    }}- (void)handleResult:(AVMetadataMachineReadableCodeObject *)metadataObject{    NSLog(@"%@", metadataObject.type);    if([metadataObject.type isEqualToString:AVMetadataObjectTypeQRCode])        NSLog(@"QR code");    else        NSLog(@"other code");        NSString *captureStr = metadataObject.stringValue;    NSLog(@"%@",captureStr);        //if the string is URL, then push a view and open the website, otherwise just pop a dialog to show the msg    if([self isURL:captureStr])    {        BrowserViewController *browserViewController = [[BrowserViewController alloc] init];        browserViewController.urlStr = captureStr;                [self.navigationController pushViewController:browserViewController animated:YES];    }    else    {        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"scan result"                                                        message:captureStr                                                       delegate:nil                                              cancelButtonTitle:@"ok"                                              otherButtonTitles: nil];        [alert show];    }}//use regular expression to recognize URL- (BOOL)isURL:(NSString *)str{    NSString *regex = @"[a-zA-z]+://[^s]*";    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];    return [predicate evaluateWithObject:str];}- (void)didReceiveMemoryWarning{    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end

其中二维码识别较灵敏，条形码稍显迟钝。

源代码下载

csdn：二维码扫码

github：ScanCode