B4J Question How to convert base64String to Image and save

Johan Schoeman said:

There is an example in the code in this posting

QR Code - "Store" image/bitmap in a QR Code

See attached B4A project: 1. It takes an image (png or jpg) and convert it into a byte array 2. The byte array is converted into a Base64 String 3. The String is then converted into a QR Code (bitmap) 4. Use the QR Code bitmap and decodes it into a string (Base64) 5. Convert the Base64 string...

www.b4x.com

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Erel said:

B4X:

Dim su As StringUtils
Dim b() As Byte = su.DecodeBase64(...)
File.WriteBytes(.., .., b)

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Dim su As StringUtils
Dim b() As Byte = su.DecodeBase64(b64string)
File.WriteBytes(File.Combine(File.DirApp, "www/assets/images/"), $"filename.png"$, b)

Erel said:

This code will fail if multiple clients upload files at one. I don't know whether it is relevant to your user case or not...

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Erel said:

You need to use a unique file name for each request. Otherwise the file will be overwritten

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dim filename as string = req.getparameter("filename")
Dim su As StringUtils
Dim b() As Byte = su.DecodeBase64(b64string)
File.WriteBytes(File.Combine(File.DirApp, "www/assets/images/"), $"${filename}.png"$, b)