// digit etc -> false

function checkDigitOnly( digitChar ) {  
    
    if ( digitChar == null ) return false ;
       
    for(var i=0;i<digitChar.length;i++){          
       var c=digitChar.charCodeAt(i);       
       if( !(  0x30 <= c && c <= 0x39 ) ) {         
        return false ;       
       }
     }
    return true ;
}



// express money
 function express_money(num){
    var numData = "";
    var startRealNum = 0;
    var sign = "";//+ ->[], - ->[-]
    numData = num;
    
    numData = numData.toString().replace(/\$|\,/g,'');
    
    if( isNaN(numData) ){
        numData = "";
        return numData;
    }
    if( numData.substring(0,1) == "-" ){
        sign = "-";
        numData = numData.substring(1);
    }
    
    // "000.." remove
    for( var i=0; i < numData.length; i++ ){
        if( numData.charAt(i) !='0' ){
            break;
        }
        startRealNum++;
    }
    
    if( numData.length != 1 && startRealNum > 0 ){
        if( numData.charAt(startRealNum) == '.' ){
            numData = numData.substring(startRealNum-1);
        }else{
            numData = numData.substring(startRealNum);
        }
    }
    
	//0.00.. remove
    if( numData.charAt(0) == "." ){
        numData = "0." + numData.substring(1);
    }
    
    tmpNum = numData.split('.');
    if( tmpNum.length ==1 ){
        numData = tmpNum[0];
        cents = "";
    }else if( tmpNum.length == 2 ){
        numData = tmpNum[0];
        cents   = tmpNum[1];
    }else{
        return "";
    }
 
    for( var i=0; i < Math.floor((numData.length-(1+i))/3); i++ )
        numData = numData.substring(0,numData.length-(4*i+3))+','+numData.substring(numData.length-(4*i+3));
 
    if( cents == "" ){
        return sign + numData;
    }else{
        return sign + (numData + "." + cents);
    }
}