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copied!<p>(<strong>Update</strong> Please see the 2nd half of this answer, where I have (hopefully) provided a more complete solution.)</p> <p>I also ran into this issue, the following works for me in FF 6 (for one direction):</p> <pre><code>var buf = new ArrayBuffer( 10 ); var view = new Uint8Array( buf ); view[ 3 ] = 4; alert(Array.prototype.slice.call(view).join("")); </code></pre> <p>Unfortunately, of course, you end up with ASCII text representations of the values in the array, rather than characters. It still (should be) much more efficient than a loop, though. eg. For the example above, the result is <code>0004000000</code>, rather than several null chars & a chr(4).</p> <p><strong>Edit:</strong></p> <p>After looking on <strong>MDC</strong> <a href="https://developer.mozilla.org/en/JavaScript_typed_arrays/Uint8Array">here</a>, you may create an <code>ArrayBuffer</code> from an <code>Array</code> as follows:</p> <pre><code>var arr = new Array(23); // New Uint8Array() converts the Array elements // to Uint8s & creates a new ArrayBuffer // to store them in & a corresponding view. // To get at the generated ArrayBuffer, // you can then access it as below, with the .buffer property var buf = new Uint8Array( arr ).buffer; </code></pre> <p>To answer your original question, this allows you to convert <code>ArrayBuffer</code> <-> <code>String</code> as follows:</p> <pre><code>var buf, view, str; buf = new ArrayBuffer( 256 ); view = new Uint8Array( buf ); view[ 0 ] = 7; // Some dummy values view[ 2 ] = 4; // ... // 1. Buffer -> String (as byte array "list") str = bufferToString(buf); alert(str); // Alerts "7,0,4,..." // 1. String (as byte array) -> Buffer buf = stringToBuffer(str); alert(new Uint8Array( buf )[ 2 ]); // Alerts "4" // Converts any ArrayBuffer to a string // (a comma-separated list of ASCII ordinals, // NOT a string of characters from the ordinals // in the buffer elements) function bufferToString( buf ) { var view = new Uint8Array( buf ); return Array.prototype.join.call(view, ","); } // Converts a comma-separated ASCII ordinal string list // back to an ArrayBuffer (see note for bufferToString()) function stringToBuffer( str ) { var arr = str.split(",") , view = new Uint8Array( arr ); return view.buffer; } </code></pre> <p>For convenience, here is a <code>function</code> for converting a raw Unicode <code>String</code> to an <code>ArrayBuffer</code> (will only work with ASCII/one-byte characters)</p> <pre><code>function rawStringToBuffer( str ) { var idx, len = str.length, arr = new Array( len ); for ( idx = 0 ; idx < len ; ++idx ) { arr[ idx ] = str.charCodeAt(idx) & 0xFF; } // You may create an ArrayBuffer from a standard array (of values) as follows: return new Uint8Array( arr ).buffer; } // Alerts "97" alert(new Uint8Array( rawStringToBuffer("abc") )[ 0 ]); </code></pre> <p>The above allow you to go from <code>ArrayBuffer</code> -> <code>String</code> & back to <code>ArrayBuffer</code> again, where the string may be stored in eg. <code>.localStorage</code> :)</p> <p>Hope this helps,</p> <p>Dan</p>

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