How to convert Bitmap to a Base64 string?
C#ImageBase64C# Problem Overview
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);
Using a richTextBox to debug, it shows:
> BM6�~
So for some reason the bytes aren't correct which causes the base64String to become null. Any idea what I'm doing wrong? Thanks.
C# Solutions
Solution 1 - C#
I found a solution for my issue:
Bitmap bImage = newImage; // Your Bitmap Image
System.IO.MemoryStream ms = new MemoryStream();
bImage.Save(ms, ImageFormat.Jpeg);
byte[] byteImage = ms.ToArray();
var SigBase64= Convert.ToBase64String(byteImage); // Get Base64
Solution 2 - C#
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;
Solution 3 - C#
No need for byte[]
...just convert the stream directly (w/using constructs)
using (var ms = new MemoryStream())
{
using (var bitmap = new Bitmap(newImage))
{
bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
var SigBase64= Convert.ToBase64String(ms.GetBuffer()); //Get Base64
}
}