<pre><code>

import "QYScanCtrl.h"

import <AVFoundation/AVFoundation.h>

import "trConst.h"

@interface QYScanCtrl ()<AVCaptureMetadataOutputObjectsDelegate,UIWebViewDelegate>

//拍摄会话

@property(nonatomic,strong)AVCaptureSession
*session;

//预览视图

@property(nonatomic,strong)AVCaptureVideoPreviewLayer
*preview;

@end

@implementation
QYScanCtrl

• (void)viewDidLoad {

  [superviewDidLoad];

  self.view.backgroundColor= [UIColorwhiteColor];

  self.title = @"防伪查询";

  //扫描

  [selfscan];

}

-(void)scan{

        //    摄像头输入设备

        //捕获设备，默认后置摄像头

        AVCaptureDevice

*device = [AVCaptureDevicedefaultDeviceWithMediaType:AVMediaTypeVideo];

        NSError *error = nil;

        //输入设备

        AVCaptureDeviceInput

*inputDevice = [AVCaptureDeviceInputdeviceInputWithDevice:device error:&error];

        //    元数据输出对象

        AVCaptureMetadataOutput

*dataOutput = [[AVCaptureMetadataOutputalloc]init];

        //    拍摄会话

        self.session = [[AVCaptureSession alloc]init];

        //    建立通道

        //先判断是否有该设备

        if ([self.session canAddInput:inputDevice])

{

            [self.session addInput:inputDevice];

        }else{

            NSLog(@"不支持该设备");

            return;


      }

        if ([self.session canAddOutput:dataOutput])

{

            [self.session addOutput:dataOutput];

        }else{

            NSLog(@"不支持该设备");

            return;
      }

        //    设置元数据输出对象相关属性

        dataOutput.metadataObjectTypes = @[@"org.iso.QRCode"];

        //    实现代理方法

        [dataOutput setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];

        //    开始扫描

        [self.session startRunning];

        //    添加预览视图

        AVCaptureVideoPreviewLayer

*preview = [AVCaptureVideoPreviewLayerlayerWithSession:self.session];

        self.preview = preview;

        //设置frame

        preview.frame = self.view.bounds;

        //添加到view图层

        [self.view.layer addSublayer:preview];

}

pragma mark --代理方法

-(void)captureOutput:(AVCaptureOutput*)captureOutput didOutputMetadataObjects:(NSArray
)metadataObjects fromConnection:(AVCaptureConnection)connection{

if(metadataObjects != nil&& [metadataObjects count] > 0) {

    AVMetadataMachineReadableCodeObject*metadataObj = [metadataObjects objectAtIndex:0];

    NSString *result;

    if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode])

{

 result = metadataObj.stringValue;

    } else {

        NSLog(@"不是二维码");
  }

    //扫描完成，停止扫描

    [self.session stopRunning];

    [self.preview removeFromSuperlayer];

     self.preview = nil;

    [self scanResult:result];

}

}

-(void)scanResult:(NSString*)result{

UIWebView*web = [[UIWebViewalloc]initWithFrame:CGRectMake(0, 64, screenW, screenH)];

[self.view addSubview:web];
//扫描完成加载结果页面
NSURL*url = [NSURLURLWithString:[NSString stringWithFormat:@"%@%@%@",HTTP_HOST_URL,HTTP_H5_SCAN,result]];
NSURLRequest*request = [NSURLRequest requestWithURL:url];
[web loadRequest:request];

}

@end