C#中图片的Base64编码与解码转换详解

using System;
using System.IO;
using System.Drawing; // 注意：在.NET Core和.NET 5+中可能需要额外的包
// 或者使用 System.Text.Encoding 和 File.ReadAllBytes 而不是 Image 类

class Program
{
    static void Main()
    {
        string imagePath = "图片.jpg";
        string base64String = ImageToBase64(imagePath, ImageFormat.Jpeg);
        Console.WriteLine(base64String);
    }

    static string ImageToBase64(string imagePath, ImageFormat format)
    {
        using (Image image = Image.FromFile(imagePath))
        {
            using (MemoryStream ms = new MemoryStream())
            {
                // 将图片保存到内存流中
                image.Save(ms, format);
                // 将内存流转换为字节数组
                byte[] imageBytes = ms.ToArray();
                // 将字节数组转换为Base64字符串
                string base64String = Convert.ToBase64String(imageBytes);
                return base64String;
            }
        }
    }
}

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string imagePath = "图片.jpg";
        string base64String = ConvertImageToBase64(imagePath);
        Console.WriteLine(base64String);
    }

    static string ConvertImageToBase64(string imagePath)
    {
        byte[] imageBytes = File.ReadAllBytes(imagePath);
        string base64String = Convert.ToBase64String(imageBytes);
        return base64String;
    }
}

using System;
using System.Drawing; // 注意：在.NET Core和.NET 5+中可能需要额外的包
using System.IO;

class Program
{
    static void Main()
    {
        string base64String = "Base64字符串";
        string outputPath = "输出图片.jpg";
        Base64ToImage(base64String, outputPath);
    }

    static void Base64ToImage(string base64String, string outputPath)
    {
        byte[] imageBytes = Convert.FromBase64String(base64String);
        using (MemoryStream ms = new MemoryStream(imageBytes))
        {
            Image image = Image.FromStream(ms);
            image.Save(outputPath, ImageFormat.Jpeg); // 可以根据需要更改格式
        }
    }
}

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string base64String = "Base64字符串";
        string outputPath = "输出图片.jpg";
        SaveBase64AsImage(base64String, outputPath);
    }

    static void SaveBase64AsImage(string base64String, string outputPath)
    {
        byte[] imageBytes = Convert.FromBase64String(base64String);
        File.WriteAllBytes(outputPath, imageBytes);
    }
}