function htmlspecialchars (string, quote_style, charset, double_encode) {
var optTemp = 0,i = 0,noquotes = false;
if (typeof quote_style === 'undefined' || quote_style === null) {
quote_style = 2;
}
string = string+'';
if (double_encode !== false) { // Put this first to avoid double-encoding
string = string.replace(/&/g, '&');
}
string = string.replace(/</g, '<').replace(/>/g, '>');
var OPTS = {
'ENT_NOQUOTES': 0,
'ENT_HTML_QUOTE_SINGLE': 1,
'ENT_HTML_QUOTE_DOUBLE': 2,
'ENT_COMPAT': 2,
'ENT_QUOTES': 3,
'ENT_IGNORE': 4
};
if ( quote_style === 0 ) {
noquotes = true;
}
if (typeof quote_style !== 'number') { // Allow for a single string or an array of string flags
quote_style = [].concat(quote_style);
for (i = 0; i < quote_style.length; i++) {
// Resolve string input to bitwise e.g. 'ENT_IGNORE' becomes 4
if (OPTS[quote_style[i]] === 0) {
noquotes = true;
}else if (OPTS[quote_style[i]]) {
optTemp = optTemp | OPTS[quote_style[i]];
}
}
quote_style = optTemp;
}
if (quote_style & OPTS.ENT_HTML_QUOTE_SINGLE) {
string = string.replace(/'/g, ''');
}
if (!noquotes) {
string = string.replace(/"/g, '"');
}
return string;
}