Zig

Extract data:image/png;base64 from HTML

See more Base64 Examples

Demonstrates how to extract base64 image data from HTMl and save to files. Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    const sb = try chilkat.StringBuilder.init();
    defer sb.deinit();
    const bd = try chilkat.BinData.init();
    defer bd.deinit();
    const sb_filename = try chilkat.StringBuilder.init();
    defer sb_filename.deinit();
    var index: i32 = 1;

    try sb.loadFile("qa_data/html/oresp body.txt", "utf-8");
    // Assume success.
    std.debug.print("length = {d}\n", .{sb.getLength()});

    var may_have_more: bool = true;
    while (may_have_more) {
        // Get the base64 between the 1st occurrence "data:image/png;base64," and "'"
        const s_base64 = try sb.getBetween(alloc, "data:image/png;base64,", "'");

        // If nothing is found, then we'll exit the loop because there are no more.
        may_have_more = sb.getLastMethodSuccess();

        if (sb.getLastMethodSuccess()) {
            // Found something.
            // Load into bd and save.
            try bd.loadEncoded(s_base64, "base64");

            sb_filename.setString("qa_output/png_") catch {};
            sb_filename.appendInt(index) catch {};
            sb_filename.append(".png") catch {};

            bd.writeFile(try sb_filename.getAsString(alloc)) catch {};

            // Replace "data:image/png;base64" with "data:image-png;base64" so the next iteration finds the next occurrence.
            sb.replaceFirst("data:image/png;base64", "data:image-png;base64") catch {};
        }

        index = index + 1;
    }

    // Restore our replacements..
    _ = sb.replace("data:image-png;base64", "data:image/png;base64");

    std.debug.print("All done.\n", .{});
}