如何位图转换成Base64的字符串？ [英] How to convert Bitmap to a Base64 string?

问题描述

我试图捕捉屏幕，然后将其转换为一个Base64字符串。这是我的code：

I'm trying to capture the screen and then convert it to a Base64 string. This is my code:

Rectangle bounds = Screen.GetBounds(Point.Empty);
Bitmap bitmap = new Bitmap(bounds.Width, bounds.Height);

using (Graphics g = Graphics.FromImage(bitmap))
{
   g.CopyFromScreen(Point.Empty, Point.Empty, bounds.Size);
}

// Convert the image to byte[]
System.IO.MemoryStream stream = new System.IO.MemoryStream();
bitmap.Save(stream, System.Drawing.Imaging.ImageFormat.Bmp);
byte[] imageBytes = stream.ToArray();

// Write the bytes (as a string) to the textbox
richTextBox1.Text = System.Text.Encoding.UTF8.GetString(imageBytes);

// Convert byte[] to Base64 String
string base64String = Convert.ToBase64String(imageBytes);

使用一个RichTextBox调试，它表明：

Using a richTextBox to debug, it shows:

BM6〜

因此​​，对于某种原因字节不正确从而导致base64String变成空。任何想法，我做错了什么？谢谢你。

So for some reason the bytes aren't correct which causes the base64String to become null. Any idea what I'm doing wrong? Thanks.

推荐答案

你的人物做 System.Text.Encoding.UTF8.GetString（imageBytes）将（几乎可以肯定）包含不可打印的字符。这可能会导致你只能看到那几个字符。如果先将其转换为一个base64字符串，那么它将只包含可打印字符，可以在文本框中显示：

The characters you get by doing System.Text.Encoding.UTF8.GetString(imageBytes) will (almost certainly) contain unprintable characters. This could cause you to only see those few characters. If you first convert it to a base64-string, then it will contain only printable characters and can be shown in a text box:

// Convert byte[] to Base64 String
string base64String = Convert.ToBase64String(imageBytes);

// Write the bytes (as a Base64 string) to the textbox
richTextBox1.Text = base64String;

这篇关于如何位图转换成Base64的字符串？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！