unity图片 base64转 sprite，图片转base64

测试代码：

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

public class LoadTexture : MonoBehaviour {
    public Image ImageRef;
    //public string base64Str= "data:image/svg+xml;base64,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";
    
        //"data:image/jpg;base64," + 
    public string base64Str;
   // Use this for initialization
    void Start () {
        Texture2dToBase64(Application.dataPath + "/" +"load.png");
        Base64ToTexture2d(base64Str);
        Base64ToImag(ImageRef, base64Str);
        Base64ToImag(ImageRef, "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");


    }

    // Update is called once per frame
    void Update ()
    {
		
	}
    //base64转图片
    public string Base64ToTexture2d(string Base64STR)
    {
        Texture2D pic = new Texture2D(1111, 1111);
        byte[] data = System.Convert.FromBase64String(Base64STR);
        pic.LoadImage(data);
        byte[] bytes = pic.EncodeToPNG();

        //下面是为了方便了解图片的信息写的
        string year = System.DateTime.Now.Year.ToString();
        string month = System.DateTime.Now.Month.ToString();
        string day = System.DateTime.Now.Day.ToString();
        string hour = System.DateTime.Now.Hour.ToString();
        string minute = System.DateTime.Now.Minute.ToString();
        string secend = System.DateTime.Now.Second.ToString();
        //存储路径
        string FileFullPath = Application.dataPath/*这是获取assets前的文件路径*/ + "/" + year + "-" + month + "-" + day + "-" + hour + "-" + minute + "-" + secend + ".png";

        File.WriteAllBytes(FileFullPath, bytes);
        return FileFullPath;
    }
    //图片转base64string
    public string Texture2dToBase64(string texture2d_path)
    {
        //将图片文件转为流文件
        FileStream fs = new System.IO.FileStream(texture2d_path, System.IO.FileMode.Open, System.IO.FileAccess.Read);
        byte[] thebytes = new byte[fs.Length];

        fs.Read(thebytes, 0, (int)fs.Length);
        //转为base64string
        string base64_texture2d = Convert.ToBase64String(thebytes);
        Debug.LogError(base64_texture2d);
        base64Str = base64_texture2d;
        return base64_texture2d;

    }

public void Base64ToImag(Image imgComponent,string base64strs )
    {
        //string base64 = "data:image/svg+xml;base64,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";
        Texture2D tex2D = new Texture2D(100,100);
        try
        {
            byte[] bytes = Convert.FromBase64String(base64strs);
            tex2D.LoadImage(bytes);
            Debug.LogError("转换成功");
        }
        catch(Exception ex)
        {
            Debug.LogError("转换失败"+ex);

        }
        Sprite s = Sprite.Create(tex2D,new Rect(0,0,tex2D.width,tex2D.height),new Vector2(0.5f,0.5f));
        imgComponent.sprite = s;
        Resources.UnloadUnusedAssets();
    }
}