remove registered symbols

HTML

<input type="text" id="safwan"/>

JavaScript

$('#safwan').keyup( function () {
	
    var flagUni = this.value.isRegistedSymbolExist();
    
    if ( flagUni[0] ) {
    	alert('xleh ad unicode registered');
        $(this).val(flagUni[1].join(''));
        return false;
    }
	
    // buat kod demo sini
	console.log('pass');
});

String.prototype.isRegistedSymbolExist = function () {

	var splitTxt = this.split('');
	var flagUni = false;
    var newStr = [];
    
    for( var i = 0, length = splitTxt.length; i < length; i++ ) {
    	var unicodeRegistered = splitTxt[i].charCodeAt(0);
        if ( unicodeRegistered === 174 ) {
        	flagUni = !flagUni;
        }
        else
        	newStr.push(splitTxt[i]);
    } 
    
    return [flagUni, newStr];
}