Edit in JSFiddle

function GetMultiLine(sStr) {
    var s = sStr;
    s = s.replace(/function/, '');
    s = s.replace(/\(/, '');
    s = s.replace(/\)/, '');
    s = s.replace(/\{/, '');
    s = s.replace(/\}/, '', -1);
    s = s.replace(/\//, '');
    s = s.replace(/\*/, '');
    s = s.replace(/\//, '', -1);
    s = s.replace(/\*/, '', -1);
    
    return s;
}

var f = function () {
    /*
    the
    quick
    brown
    fox
    jumps
    over
    the lazy dog
    */
};

//使用方式
alert(GetMultiLine(new String(f)));