1.二維碼常見的生成與識別途徑

1.草料二維碼 https://cli.im/text

2.在軟件中實現生成和掃描二維碼 使用zxing實現

zxing是一個用java寫的開源項目，zxing.net是移植到.net工程上的。

https://github.com/micjahn/ZXing.Net

2.實現二維碼的識別

1.Unity工程

2.讓RawImage顯示攝像頭內容

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using ZXing;
using UnityEngine.UI;

public class QRCodeTest : MonoBehaviour {
    public RawImage cameraTexture;

    private WebCamTexture webCamTexture;
	// Use this for initialization
	void Start () {
        WebCamDevice[] devices = WebCamTexture.devices;
        string deviceName = devices[0].name;
        webCamTexture = new WebCamTexture(deviceName, 400, 300);
        cameraTexture.texture = webCamTexture;
        webCamTexture.Play();
	}
	
	// Update is called once per frame
	void Update () {
		
	}
}

3.掃描功能實現代碼（代碼有點長，慢慢看）

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using ZXing;
using UnityEngine.UI;

public class QRCodeTest : MonoBehaviour {
    public RawImage cameraTexture;//存儲攝像頭拍到的內容

    private WebCamTexture webCamTexture;//攝像頭的內容

    Color32[] data;

    BarcodeReader barcodeReader;//Zxing提供的讀取攝像頭內容的方法

    float interval = 0f;//做定時器用
	// Use this for initialization
	void Start () {
        //打開了攝像頭
        WebCamDevice[] devices = WebCamTexture.devices;
        string deviceName = devices[0].name;
        webCamTexture = new WebCamTexture(deviceName, 400, 300);
        cameraTexture.texture = webCamTexture;
        webCamTexture.Play();

        barcodeReader = new BarcodeReader();
	}
	
	// Update is called once per frame
	void Update () {
        interval += Time.deltaTime;
        if (interval >= 3f) {
            ScanQRCode();
            interval = 0f;
        }
	}

    void ScanQRCode()
    {
        //GetPixels32是把格式轉換為Color32的方法
        data = webCamTexture.GetPixels32();
        //result存儲讀取的內容
        var result = barcodeReader.Decode(data, webCamTexture.width, webCamTexture.height);

        if (result != null) {
            Debug.Log(result.Text);
        }
    }
}

3.實現二維碼的生成 (註：我關掉網絡也能成功識別生成的二維碼，說明這東西是離線的)

1.新建一個RawImage存儲生成的識別圖

2.添加了生成二維碼的方法：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using ZXing;
using UnityEngine.UI;

public class QRCodeTest : MonoBehaviour {
    public RawImage cameraTexture;//存儲攝像頭拍到的內容
    public RawImage QRCode;//存儲生成的二維碼

    private WebCamTexture webCamTexture;//攝像頭的內容

    Color32[] data;

    BarcodeReader barcodeReader;//Zxing提供的讀取攝像頭內容的方法
    BarcodeWriter barcodeWriter;//Zxing提供的寫內容的方法

    float interval = 0f;//做定時器用
	// Use this for initialization
	void Start () {
        //打開了攝像頭
        WebCamDevice[] devices = WebCamTexture.devices;
        string deviceName = devices[0].name;
        webCamTexture = new WebCamTexture(deviceName, 400, 300);
        cameraTexture.texture = webCamTexture;
        webCamTexture.Play();

        barcodeReader = new BarcodeReader();
	}
	
	// Update is called once per frame
	void Update () {
        interval += Time.deltaTime;
        if (interval >= 3f) {
            ScanQRCode();
            interval = 0f;
        }

        //按下空格鍵生成二維碼
        if (Input.GetKeyDown(KeyCode.Space))
        {
            //在這種寫法裏 只能填入256
            ShowQRCode("我愛學習", 256, 256);
            //如果想要其他大小的二維碼呢？見文章底部鏈接
        }
	}

    //掃描二維碼方法
    void ScanQRCode()
    {
        //GetPixels32是從一張圖片上獲取顏色的方法
        data = webCamTexture.GetPixels32();
        //result存儲讀取的內容
        var result = barcodeReader.Decode(data, webCamTexture.width, webCamTexture.height);

        if (result != null) {
            Debug.Log(result.Text);
        }
    }

    //顯示生成的二維碼
    void ShowQRCode(string str,int width,int height) {
        //定義texture2d並且填充
        Texture2D t = new Texture2D(width, height);
        t.SetPixels32(GeneQRCode(str, width, height));
        t.Apply();

        QRCode.texture = t;
    }

    //返回Color32圖片顏色的方法
    Color32[] GeneQRCode(string formatStr,int width,int height) {

        ZXing.QrCode.QrCodeEncodingOptions options = new ZXing.QrCode.QrCodeEncodingOptions();
        options.CharacterSet = "UTF-8";//設置字符編碼，否則中文不能顯示
        options.Width = width;
        options.Height = width;
        options.Margin = 1;//二維碼距離邊緣的空白

        barcodeWriter = new BarcodeWriter { Format = ZXing.BarcodeFormat.QR_CODE, Options = options };

        return barcodeWriter.Write(formatStr);
    }
}

更多：

ZXing 二維碼生成的坑 http://blog.sina.com.cn/s/blog_6ad33d350102xj8l.html

zxing.net讀取和保存二維碼，設置中文字符集，讀取中文二維碼 https://bbs.csdn.net/topics/391950715?page=1

Unity插件系列之二維碼