| <!DOCTYPE html> |
| <head> |
| <title>Text Encoding Workaround</title> |
| <style> |
| div { |
| background-color: rgb(200, 200, 200); |
| height: 50px; |
| } |
| </style> |
| </head> |
| <body> |
| <div id="text-decoded"> </div> |
| <div id="text-encoded"> </div> |
| <div id="large-string-encode"> </div> |
| <div id="large-string-decode"> </div> |
| <script> |
| /* |
| Text encoding is not natively supported by Cobalt. |
| There is work in progress to support it in Cobalt 22.lts. |
| |
| In the mean time, a workaround is presented here, that could be |
| used to encode/decode to/from UTF-8. |
| |
| The full IDL definition can be found at: |
| https://cobalt.googlesource.com/cobalt/+/refs/heads/21.lts.1+/src/cobalt/fetch/fetch_internal.idl, |
| ant it is available in 19.lts.1+ versions. |
| |
| **WARNING:** As mentioned in the IDL file, the utility was not |
| meant to be public and should not be used outside of the fetch |
| implementation. |
| |
| **WARNING:** Even when this is a native implementation it might still |
| not be ideal to handle very large strings due to its performance. |
| |
| **WARNING:** DecodeFromUTF8 throws a simple TypeError exception |
| when the data provided is not a valid utf-8. |
| */ |
| |
| // Using FetchInternal.decodeFromUTF8 |
| var arr = new Uint8Array( |
| [ 228, 189, 160, 229, 165, 189, 239, 188, 140, 228, |
| 184, 150, 231, 149, 140, 33, 32, 208, 159, 209, |
| 128, 208, 184, 208, 178, 208, 181, 209, 130, 32, |
| 208, 188, 208, 184, 209, 128, 33, 32, 72, 101, |
| 108, 108, 111, 32, 119, 111, 114, 108, 100, 33]); |
| var utf8_string = FetchInternal.decodeFromUTF8(arr); |
| document.getElementById("text-decoded").innerHTML = utf8_string; |
| |
| // Using FetchInternal.encodeToUTF8 |
| var str = "你好，世界! Привет мир! Hello world!"; |
| var u8_arr = FetchInternal.encodeToUTF8(str); |
| document.getElementById("text-encoded").innerHTML = u8_arr.toString(); |
| |
| // Trying very large strings; |
| // Note: This section takes a while for this to be completed. |
| var kSize = 1048576; // 8 x 1024 x 128 |
| var char = "c"; |
| var large_str = char.repeat(kSize); |
| var u8_large_arr = FetchInternal.encodeToUTF8(large_str); |
| document.getElementById("large-string-encode").innerHTML = u8_large_arr.toString(); |
| var large_decoded_str = FetchInternal.decodeFromUTF8(u8_large_arr); |
| document.getElementById("large-string-decode").innerHTML = large_decoded_str; |
| </script> |
| </body> |
| </html> |
