首先，如果这违反了规则，或者对此感到不满，我非常抱歉并且可以随意关闭/关闭。我拼命地卡住了。
我在编写的HTML页面遇到问题，该页面应该包含具有特定要求的输入，添加div以显示错误消息，并自动更新这些错误消息onblur。这项任务是为了测试我们的javascript技能，因此必须通过javascript完全验证。
以下是一些指导原则......
验证四个单独的表单：
当违反其中任何一个时，我应该停用表单的提交按钮，使其无法点击并添加一个孩子＆＃34; div＆＃34;错误显示包含描述情况的错误消息。
代码看起来对我来说是正确的，而且是自发的，但我相信，因为javascript一次只能查看一行，所以它不能正确显示错误消息，甚至根本无法访问代码的某些部分。< / p>
这是我的大量javascript代码，我主要是想找到一种方法来突破我的代码似乎陷入的if / else块：
function formValidation() {
var form = document.getElementById('project-form');
var username = document.getElementById('username');
var name = document.getElementById('name');
var phone = document.getElementById('phone-number');
var email = document.getElementById('email');
var password = document.getElementById('password');
var passwordConfirmation = document.getElementById('password-confirmation');
var submit = document.getElementById('submit-btn');
var errorDisplay = document.getElementById('error-display');
var missingFieldBoolean = false;
var passwordMismatchBoolean = false;
var isUpper = false;
var isNumber = false;
var passwordLength = false;
var validEmail = false;
var createDiv = document.createElement("DIV");
var passwordConstraint, passwordConstraintError;
var mailformat = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;
//Checks all fields for empty values and updates error div
if (username.value.length == 0 || name.value.length == 0 || email.value.length == 0 || password.value.length == 0 || passwordConfirmation.value.length == 0) {
missingField = errorDisplay.appendChild(createDiv);
missingField.setAttribute("id", "required-field-error");
missingFieldError = document.getElementById('required-field-error');
missingFieldError.innerHTML = "Missing Fields: ";
if (username.value.length == 0) {
missingFieldError.innerHTML += "Username - ";
}
if (name.value.length == 0) {
missingFieldError.innerHTML += "Full Name - ";
}
if (email.value.length == 0) {
missingFieldError.innerHTML += "Email - ";
}
if (password.value.length == 0) {
missingFieldError.innerHTML += "Password - ";
}
if (passwordConfirmation.value.length == 0) {
missingFieldError.innerHTML += "Password Confirmation - ";
}
} else {
errorDisplay.removeChild(missingFieldError);
missingFieldBoolean = true;
}
//Checks password vs password confirmation to see if they match, else updates error div
if (password.value != passwordConfirmation.value) {
passwordMismatch = errorDisplay.appendChild(createDiv);
passwordMismatch.setAttribute("id", "password-mismatch-error");
passwordMismatchError = document.getElementById('password-mismatch-error');
passwordMismatchError.innerHTML = "The Password and Password Confirmation do not match. Please re-enter.";
} else {
errorDisplay.removeChild(passwordMismatchError);
passwordMismatchBoolean = true;
}
//for loop to iterate through password to check for required characters, else updates error div
for (var index = 0; index < password.value.length; index++) {
if (password.value.charAt(index) == password.value.charAt(index).toUpperCase) {
isUpper = true;
}
if ("0123456789".indexOf(password.value.charAt(index)) > -1) {
isNumber = true;
}
if (password.value.length > 7) {
passwordLength = true;
} else {
passwordConstraint = errorDisplay.appendChild(createDiv);
passwordConstraint.setAttribute("id", "password-constraint-error");
passwordConstraintError = document.getElementById('password-constraint-error');
passwordConstraintError.innerHTML = "The Password must be 8 characters long, with one uppercase letter and one number. ";
}
}
//checks if password constraints are met and removes div if true
if (isUpper && isNumber && passwordLength) {
errorDisplay.removeChild(passwordConstraintError);
}
//checks email, if invalid it adds error div, else it removes the div ***NOT WORKING***
if (!(mailformat.test(email.value))) {
invalidEmail = errorDisplay.appendChild(createDiv);
invalidEmail.setAttribute("id", "invalid-email-error");
invalidEmailError = document.getElementById('invalid-email-error');
invalidEmailError.innerHTML = "Please enter a valid email address.";
} else {
errorDisplay.removeChild(invalidEmailError);
validEmail = true;
}
//if all requirements are met and true, submit button becomes enabled ***NOT WORKING***
if (isUpper && isNumber && passwordLength && missingFieldBoolean && passwordMismatchBoolean && validEmail) {
submit.disabled = false;
}
}<div id="error-display"></div>
<br>
<form id="project-form" action="/submit.php" method="get" onclick="formValidation()">
<label>Username:</label>
<input id="username" type="text" onblur="formValidation()" required>
<c>*</c>
<br>
<label>Full Name:</label>
<input id="name" type="text" onblur="formValidation()" required>
<c>*</c>
<br>
<label>Phone Number:</label>
<input id="phone-number" type="tel">
<br>
<label>Email:</label>
<input id="email" type="email" onblur="formValidation()" required>
<c>*</c>
<br>
<label>Password:</label>
<input id="password" type="password" required onblur="formValidation()">
<c>*</c>
<br>
<label>Confirm Password:</label>
<input id="password-confirmation" type="password" required onblur="formValidation()">
<c>*</c>
<br>
<br>
<input id="submit-btn" type="submit" value="Submit" disabled>
</form>
非常感谢，如果我违反规则，再次感到抱歉。
答案 0 :(得分：0)
我会将所有输入放入对象中，这样就可以自动遍历对象。
const fieldValues = [
'username',
'name',
'phone-number',
'email',
'password',
'password-confirmation',
]
.reduce((fieldsSoFar, fieldName) => {
fieldsSoFar[fieldName] = document.getElementById(fieldName).value;
return fieldsSoFar;
}, {});
const missingFieldsStr =
Object.entries(fieldValues)
.filter(([, fieldValue]) => fieldValue.length === 0)
.map(([fieldName]) => {
const words = fieldName.split(' ');
const upperWords = words.map(word => word.slice(0, 1).toUpperCase() + word.slice(1))
return upperWords;
})
.join(', ');
if (missingFieldsStr) {
// display it
}
// skipping some lines...
const hasUpper = /[A-Z]/.test(fieldValues.password);
const hasNumber = /[0-9]/.test(fieldValues.password);
等等。
不要隐式创建全局变量 - 强烈考虑使用linter。
当您故意使用或插入HTML标记（可能存在安全性和编码问题）时，仅使用innerHTML。在设置或检索文本值时，请改用textContent。