造轮子：C#中将图片转化成base64字符串

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace ConvertImgToBase64
{
   class Program
   {
      static void Main(string[] args)
      {
         FileInfo file = new FileInfo("1.png");
         var stream = file.OpenRead();
         byte[] buffer = new byte[file.Length];
         //读取图片字节流
         stream.Read(buffer, 0, Convert.ToInt32(file.Length));
         //将base64字符串保存到base64.txt文件中
         StreamWriter sw = new StreamWriter("base64.txt",false, Encoding.UTF8);
         //将字节流转化成base64字符串
         sw.Write(Convert.ToBase64String(buffer));
         sw.Close();
         Console.WriteLine("Convert successful!");
         Console.Read();
      }
   }
}

.main {
    width: 600px;
    height: 300px;
    background-image:url(data:image/gif;base64,R0lGODlhCAAIAJEAAOnp6eTk5O7m8AAAACH5BAEAAAIALAAAAAAIAAgAAAINjAMJh2q6DnxOVsqmLQA7);
}

<img src="data:image/jpeg;base64,R0lGODlhCAAIAJEAAOnp6eTk5O7m8AAAACH5BAEAAAIALAAAAAAIAAgAAAINjAMJh2q6DnxOVsqmLQA7" alt="Base64 encoded image" />