[英]ERROR in jQuery for some reason and I can't figure out why
app.js:
//Hide hints
$("form span").css("display", "none");
//create som variables to make the code easier to follow
var $password = $("#password");
var $confirmPassword = $("#confirmPassword");
//when focusing (clicking) on the password text input, show the
//hints until the length of the input reaches 8.
//specifies whether the password specified is long enough
function passwordIEnough() {
return $(this).val().length > 8;
}
//specifies if the password and confirm password boxes are equal
function passwordsAreEqual() {
return $password.val() === $confirmPassword.val();
}
function passwordEvent() {
if ( passwordIsEnough() ) {
$(this).next().css("display", "none");
} else {
$(this).next().css("display", "inline-block");
}
}
function confirmPasswordEvent() {
if ( passwordsAreEqual() ) {
$(this).next().css("display", "none");
} else {
$(this).next().css("display", "inline-block");
}
}
的HTML:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Dropdown</title>
<link rel="stylesheet" href="css/style.css" charset="utf-8">
</head>
<body>
<form action="#" method="post">
<h2>Professional Form</h2>
<label for="username">Username</label>
<input type="text" id="uname" name="username">
<label for="password">Password</label>
<input type="password" id="password" name="password">
<!-- <div class="arrow-left"></div> -->
<span>Atleast 8 characters</span>
<label for="confirmPassword">Confirm Password</label>
<input type="password" id="confirmPassword" name="confirmPassword">
<!-- <div class="arrow-left"></div> -->
<span>Please confirm your password</span>
<input type="submit" value="Submit" id="submit">
</form>
<script src="https://code.jquery.com/jquery-1.12.4.min.js" integrity="sha256-ZosEbRLbNQzLpnKIkEdrPv7lOy9C27hHQ+Xp8a4MxAQ=" crossorigin="anonymous"></script>
<script src="js/app.js" type="text/javascript" charset="utf-8"></script>
</body>
</html>
$password.focus(passwordEvent).keyup(passwordEvent).focus(confirmPasswordEvent).keyup(confirmPasswordEvent);
$confirmPassword.focus(confirmPasswordEvent).keyup(confirmPasswordEvent);
控制台說什么:
未捕獲的TypeError:無法讀取未定義的jquery-1.12.4.min.js:4的屬性'toLowerCase'
問題在於您的情況下的“ this”是對窗口的引用,而不是您期望的對文本框的引用。 $(this)僅在綁定的事件處理程序內工作。 嘗試使用其他訪問文本框的方法,例如$("#password").val()
,或將$("#password").focus(function(){})
用於您的邏輯。
在passwordEvent和ConfirmPasswordEvent中,“ this”是導致事件的HtmlInputElement,它通過jQuery事件處理程序傳遞。
我認為此范圍不會傳遞給“ passwordIsEnough”,並且“ this”范圍可能是Windows。 使用您的瀏覽器調試工具在調試點點擊它。
您也可以使用“ passwordIsEnough.call(this)”來調用它,以調用“ this”與調用方法具有相同作用域的方法。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.