form表单提交 type="submit"

<form action=""  method="post" onsubmit="return validte()">
<div class="regist-top">
<ul class="regist-form">
<li><label for="">姓 名</label><input type="text" name="username" id="username">
<span class="error_info" id="name_error"></span>
</li>
<li><label for="">学 校</label><input type="text" name="school" id="school">
<span class="error_info" id="school_error"></span>
</li>
<li><label for="">手 机</label><input type="text" name="phonenumber" id="phonenumber">
<span class="error_info" id="phone_error"></span>
</li>
<li class="last">
<label for="">QQ</label><input type="text" name="qq" id="qq">
<span class="error_info" id="qq_error"></span>
</li>
</ul>
</div>
<div class="tc"><input type="submit" class="submit" value="离大使就差一步了，赶紧提交吧！"></div>
</form>

$(function(){
$("#username").on({
"blur":function(){username();},
"focus":function(){$("#name_error").text("");}
});
$("#school").on({
"blur":function(){school();},
"focus":function(){$("#school_error").text("");}
});
$("#phonenumber").on({
"blur":function(){phonenumber();},
"focus":function(){$("#phone_error").text("");}
});
$("#qq").on({
"blur":function(){ qq();},
"focus":function(){ $("#qq_error").text("");}
});
});
function validte(){

if(username() && school() && phonenumber() && qq()){
return true;
}else{
return false;
}
}
function username(){
var username=$("#username").val();
var testUsername = /^[\u4e00-\u9fa5a-zA-Z0-9]{3,12}$/.test(username);

if(username==""){
$("#name_error").text("姓名不能为空");
return false;
}else if (!testUsername) {
$("#name_error").text("姓名格式不正确");

return false;
}
return true;
}
function school(){
var school=$("#school").val();
if(school==""){
$("#school_error").text("学校不能为空");
return false;
}
return true;
}
function phonenumber(){
var phonenumber=$("#phonenumber").val();
var testPhonenumber=/^1[3|4|5|8][0-9]\d{8}$/.test(phonenumber);
if(phonenumber==""){
$("#phone_error").text("手机号不能为空");
return false;
}else if (!testPhonenumber) {
$("#phone_error").text("手机号格式不正确");
return false;
}
return true;
}
function qq(){
var qq=$("#qq").val();
var testQQ=/^\d{5,10}$/.test(qq);
if(qq==""){
$("#qq_error").text("qq不能为空");
return false;
}else if (!testQQ) {
$("#qq_error").text("qq格式不正确");
return false;

}
return true;
}