我正在尝试使用 Javascript 验证表单，但密码长度检查不起作用，但从我所看到的代码中没有明显的错误。
形式：
<form id="reg_form" onsubmit="return false;">
<input type="text" maxlength="255" placeholder="Email..." name="email" /><br />
<input type="password" placeholder="Password..." name="password" /><br />
<input type="text" maxlength="30" placeholder="Username..." name="username" /><br />
<input type="text" maxlength="255" placeholder="First Name..." name="fname" /><br />
<input type="text" maxlength="255" placeholder="Last Name..." name="lname" /><br />
<!-- Start Div With reCaptcha In -->
<!-- End Div With reCaptcha In -->
<input type="submit" value="Sign-up" onclick="register(this.form, this.form.email, this.form.password, this.form.username, this.form.fname, this.form.lname);" />
</form>
Javascript函数：
<script>
function register(form, email, password, username, fname, lname) {
document.getElementById("reg_error").style.display = "block";
if (email.value.length < 1) {
document.getElementById("reg_error").innerHTML = "Please Enter An Email Address!";
return;
}
if (password.value.length < 6) {
document.getElementById("reg_error").innerHtml = "Passwords Must Be Longer Than 6 Characters!";
return;
}
if (username.value.length < 5 || username.value.length > 30) {
document.getElementById("reg_error").innerHTML = "Username Must Be Between 5 And 30 Characters Long!";
return;
}
if (fname.value.length < 1) {
document.getElementById("reg_error").innerHTML = "Please enter a first name!";
return;
}
if (lname.value.length < 1) {
document.getElementById("reg_error").innerHTML = "Please enter a last name!";
return;
}
var info = new FormData();
info.append("email", email.value);
info.append("p", hex_sha512(password.value));
password.value = "";
info.append("username", username.value);
info.append("fname", fname.value);
info.append("lname", lname.value);
if (window.XMLHttpRequest) {
register_ = new XMLHttpRequest();
} else {
register_ = new ActiveXObject("Microsoft.XMLHTTP");
}
register_.onreadystatechange = function () {
if (register_.readyState == 4 && register_.status == 200) {
document.getElementById("reg_error").innerHTML = register_.responseText;
}
}
register_.open("POST", "scripts/signup.php", true);
register_.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
register_.send(info);
}
</script>
除了查询密码值长度的语句之外，所有 if 语句都能正常工作。任何帮助，将不胜感激。当我通过 console.log() 测试它们时，这些值被正确传递；
我正在使用 HTML5 样板。我不想使用 jQuery 来做到这一点。