var format = /[ `!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?~]/;
//            ^                                       ^   
document.write(format.test("My@string-with(some%text)") + "
");
document.write(format.test("My string with spaces") + "
");
document.write(format.test("MyStringContainingNoSpecialChars"));