Library

Base64Helper

Base64Helper

Saving Decoded Data

Methods for saving Base64-decoded bytes to a file and guessing the correct file extension from binary content.

Methods for saving Base64-decoded bytes to a file and guessing the correct file extension from binary content.

SaveTo writes the decoded bytes from the Base64 input (set via WithInput) to the specified GPALFile path. If the filename has no extension or has a generic one, GPAL uses the GuessExtensionFromBytes result to determine the correct extension. GuessExtensionFromBytes inspects the first few bytes of binary data (magic bytes) to determine the file type - returns a string like '.pdf', '.png', or '.zip'.

Examples

GPAL Fluent: High-level fluent C# API

//GuessExtensionFromBytes reads the file signature (magic bytes at the start of the data) to identify the format. It handles common formats like PDF, PNG, JPEG, GIF, ZIP, and Office documents.

// Decode and save, letting GPAL pick the extension GPAL.Base64 .WithInput(base64FileData) .SaveTo(GPAL.FileFor("C:\downloads\file")); // GPAL auto-detects extension from bytes // Manually guess the extension from bytes byte[] fileBytes = Convert.FromBase64String(base64String); string ext = GPAL.Base64.GuessExtensionFromBytes(fileBytes); string path = $"C:\output\document{ext}"; GPAL.Base64 .WithInput(base64String) .SaveTo(GPAL.FileFor(path));

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Base64Helper
Saving Decoded Data
  • Examples