iOS实现二维码的扫描功能

直接上代码，就不多废话了
//// ViewController.m// QRCode//// Created by chenchen on 15/7/30.// Copyright （c） 2015年 BSY. All rights reserved.//#import <AVFoundation/AVFoundation.h>#import "ViewController.h"@interface ViewController （）<AVCaptureMetadataOutputObjectsDelegate> @end @implementation ViewController - （void）viewDidLoad {[super viewDidLoad];AVCaptureSession *session = [[AVCaptureSession alloc] init];AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];NSError *error = nil; AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:deviceerror:&error];if （input） {[session addInput:input];} else {NSLog（@"Error: %@", error）;}AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];//设置扫码支持的编码格式（如下设置条形码和二维码兼容）[output setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code]];[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue（）];[session addOutput:output];[session startRunning];} #pragma mark - AVCaptureMetadataOutputObjectsDelegate- （void）captureOutput:（AVCaptureOutput *）captureOutputdidOutputMetadataObjects:（NSArray *）metadataObjectsfromConnection:（AVCaptureConnection *）connection{NSString *QRCode = nil;for （AVMetadataObject *metadata in metadataObjects） {if （[metadata.type isEqualToString:AVMetadataObjectTypeQRCode]） {// This will never happen; nobody has ever scanned a QR code... everQRCode = [（AVMetadataMachineReadableCodeObject *）metadata stringValue];break;}} NSLog（@"QR Code: %@", QRCode）;}- （void）didReceiveMemoryWarning {[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.} @end