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<!-- http://emilsblog.lerch.org/2009/07/javascript-hacks-using-xhr-to-load.html -->
<html>
<head>
<script language="vbscript">
Function BinaryArrayToAscCSV( aBytes )
Dim j, sOutput
sOutput = "BinaryArrayToAscCSV"
For j = 1 to LenB(aBytes)
sOutput= sOutput & AscB( MidB(aBytes,j,1) )
sOutput= sOutput & ","
Next
BinaryArrayToAscCSV = sOutput
End Function
</script>
<script type="text/javascript">
Base64 = {
// private property
_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
encodeBinaryArrayAsString : function(input) {
var ascArr;
var output = "";
var bytebuffer;
var encodedCharIndexes = new Array(4);
var inx = 0;
ascArr = input.substring("BinaryArrayToAscCSV".length, input.length - 1).split(',');
while(inx < ascArr.length) {
// Fill byte buffer array
bytebuffer = new Array(3);
for(jnx = 0; jnx < bytebuffer.length; jnx++) {
if(inx < ascArr.length) {
bytebuffer[jnx] = parseInt(ascArr[inx++]);
} else {
bytebuffer[jnx] = 0;
}
}
// Get each encoded character, 6 bits at a time
// index 1: first 6 bits
encodedCharIndexes[0] = bytebuffer[0] >> 2;
// index 2: second 6 bits (2 least significant bits from input byte 1 + 4 most significant bits from byte 2)
encodedCharIndexes[1] = ((bytebuffer[0] & 0x3) << 4) | (bytebuffer[1] >> 4);
// index 3: third 6 bits (4 least significant bits from input byte 2 + 2 most significant bits from byte 3)
encodedCharIndexes[2] = ((bytebuffer[1] & 0x0f) << 2) | (bytebuffer[2] >> 6);
// index 3: forth 6 bits (6 least significant bits from input byte 3)
encodedCharIndexes[3] = bytebuffer[2] & 0x3f;
// Determine whether padding happened, and adjust accordingly
paddingBytes = inx - (ascArr.length - 1);
switch(paddingBytes) {
case 2:
// Set last 2 characters to padding char
encodedCharIndexes[3] = 64;
encodedCharIndexes[2] = 64;
break;
case 1:
// Set last character to padding char
encodedCharIndexes[3] = 64;
break;
default:
break; // No padding - proceed
}
// Now we will grab each appropriate character out of our keystring
// based on our index array and append it to the output string
for(jnx = 0; jnx < encodedCharIndexes.length; jnx++) {
output += this._keyStr.charAt(encodedCharIndexes[jnx]);
}
}
return output;
},
encodeBinary : function(input){
var output = "";
var bytebuffer;
var encodedCharIndexes = new Array(4);
var inx = 0;
var paddingBytes = 0;
while(inx < input.length){
// Fill byte buffer array
bytebuffer = new Array(3);
for(jnx = 0; jnx < bytebuffer.length; jnx++) {
if(inx < input.length) {
bytebuffer[jnx] = input.charCodeAt(inx++) & 0xff; // throw away high-order byte, as documented at: https://developer.mozilla.org/En/Using_XMLHttpRequest#Handling_binary_data
} else {
bytebuffer[jnx] = 0;
}
}
// Get each encoded character, 6 bits at a time
// index 1: first 6 bits
encodedCharIndexes[0] = bytebuffer[0] >> 2;
// index 2: second 6 bits (2 least significant bits from input byte 1 + 4 most significant bits from byte 2)
encodedCharIndexes[1] = ((bytebuffer[0] & 0x3) << 4) | (bytebuffer[1] >> 4);
// index 3: third 6 bits (4 least significant bits from input byte 2 + 2 most significant bits from byte 3)
encodedCharIndexes[2] = ((bytebuffer[1] & 0x0f) << 2) | (bytebuffer[2] >> 6);
// index 3: forth 6 bits (6 least significant bits from input byte 3)
encodedCharIndexes[3] = bytebuffer[2] & 0x3f;
// Determine whether padding happened, and adjust accordingly
paddingBytes = inx - (input.length - 1);
switch(paddingBytes){
case 2:
// Set last 2 characters to padding char
encodedCharIndexes[3] = 64;
encodedCharIndexes[2] = 64;
break;
case 1:
// Set last character to padding char
encodedCharIndexes[3] = 64;
break;
default:
break; // No padding - proceed
}
// Now we will grab each appropriate character out of our keystring
// based on our index array and append it to the output string
for(jnx = 0; jnx < encodedCharIndexes.length; jnx++) {
output += this._keyStr.charAt(encodedCharIndexes[jnx]);
}
}
return output;
}
};
</script>
<script type="text/javascript">
LoadBinaryResource = function(url) {
var req = new XMLHttpRequest();
req.open('GET', url, false);
if (req.overrideMimeType) {
req.overrideMimeType('text/plain; charset=x-user-defined');
}
req.send(null);
if (req.status != 200) return '';
if (typeof(req.responseBody) !== 'undefined') return BinaryArrayToAscCSV(req.responseBody);
return req.responseText;
}
LoadBinaryResourceAsBase64 = function(url) {
var data = LoadBinaryResource(url);
if (data.indexOf("BinaryArrayToAscCSV") !== -1) {
return Base64.encodeBinaryArrayAsString(data);
} else {
return Base64.encodeBinary(data);
}
}
</script>
</head>
<body>
<script type="text/javascript">
alert(LoadBinaryResource("foo.zip"))
alert(LoadBinaryResourceAsBase64("foo.zip"))
</script>
</body>
</html>
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