JavaScript防止用户提交非法字符

function pCheck() { if (form.username.value != "") { if (!strangecode(form.username.value)) { form.username.focus(); return false; } } } //验证特殊字符 function strangecode(code) { var strangCode = "~`#%^&/'/"<>"; var temp; for (var i = 0; i<code.length; i++ ) { temp = code.substring(i,i+1); if (strangCode.indexOf(temp) !=-1) { alert("文本框中含有非法字符[ " + temp + " ]！"); return (false); } } return true; }