Fern  Wisozk

Fern Wisozk

1613792700

Optional Chaining vs Assertion Operator in TypeScript

If you have been using TypeScript, chances are you have come across the weird “?.” & “!” operators while writing code. And if you are like me, then you might have pulled your hair out trying to figure out the difference between them. Well, rest assured because after reading this article, you will have a clear picture of the two operators and the difference between them.

Before we jump to the difference between these two, let us first understand the behavior of these operators.

1. (?.) — Optional Chaining

Before we jump in to understand optional chaining, let’s take a look at this code written in JavaScript.

Image for post

JavaScript Example

In the above code, let’s say we have a data variable but we are not aware of its contents. It may be a null valueundefined, or it may have some properties. To return “data.getName()”, we first have to check whether data is not null and not undefined . Not performing this check may result in an error if the data variable is undefined or null.

Typescript makes writing code like this easy and much simpler to read. With optional chaining, the above code can be re-written in TypeScript as:

Image for post

TypeScript Example

Wasn’t that concise and clean? The star of the show in optional chaining is the "?.” operator that checks if the variable is either null or undefined.

If the "?.” operator finds that the variable is either null or undefined, TypeScript will immediately stop running the expression.

#reactjs #typescript #javascript

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Optional Chaining vs Assertion Operator in TypeScript

Cómo crear impresionantes botones de radio personalizados usando solo HTML y CSS

En esta guía, aprenderá cómo crear impresionantes botones de radio personalizados usando solo HTML y CSS. Para crear impresionantes botones de radio personalizados usando solo HTML y CSS. Primero, debe crear dos archivos, un archivo HTML y otro es un archivo CSS.

1: Primero, cree un archivo HTML con el nombre de index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Custom Radio Buttons | Codequs</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
  <div class="wrapper">
    <div class="title">Select your option</div>
    <div class="box">
      <input type="radio" name="select" id="option-1">
      <input type="radio" name="select" id="option-2">
      <input type="radio" name="select" id="option-3">
      <input type="radio" name="select" id="option-4">
      <label for="option-1" class="option-1">
        <div class="dot"></div>
        <div class="text">Gamer</div>
      </label>
      <label for="option-2" class="option-2">
        <div class="dot"></div>
        <div class="text">YouTuber</div>
      </label>
      <label for="option-3" class="option-3">
        <div class="dot"></div>
        <div class="text">Student</div>
      </label>
      <label for="option-4" class="option-4">
        <div class="dot"></div>
        <div class="text">Developer</div>
      </label>
    </div>
  </div>

</body>
</html>

2: Segundo, crea un archivo CSS con el nombre de style.css

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
}
.wrapper{
  width: 350px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 5px 5px 30px rgba(0,0,0,0.2);
}
.wrapper .title{
  color: #fff;
  line-height: 65px;
  text-align: center;
  background: #333;
  font-size: 25px;
  font-weight: 500;
  border-radius: 10px 10px 0 0;
}
.wrapper .box{
  padding: 20px 30px;
  background: #fff;
  border-radius: 10px;
}
.wrapper .box label{
  display: flex;
  height: 53px;
  width: 100%;
  align-items: center;
  border: 1px solid lightgrey;
  border-radius: 50px;
  margin: 10px 0;
  padding-left: 20px;
  cursor: default;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1,
#option-2:checked ~ .option-2,
#option-3:checked ~ .option-3,
#option-4:checked ~ .option-4{
  background: #333;
  border-color: #333;
}
.wrapper .box label .dot{
  height: 20px;
  width: 20px;
  background: #d9d9d9;
  border-radius: 50%;
  position: relative;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot,
#option-2:checked ~ .option-2 .dot,
#option-3:checked ~ .option-3 .dot,
#option-4:checked ~ .option-4 .dot{
  background: #fff;
}
.box label .dot::before{
  position: absolute;
  content: "";
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(2);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot::before,
#option-2:checked ~ .option-2 .dot::before,
#option-3:checked ~ .option-3 .dot::before,
#option-4:checked ~ .option-4 .dot::before{
  background: #333;
  transform: translate(-50%, -50%) scale(1);
}
.wrapper .box label .text{
  color: #333;
  font-size: 18px;
  font-weight: 400;
  padding-left: 10px;
  transition: color 0.3s ease;
}
#option-1:checked ~ .option-1 .text,
#option-2:checked ~ .option-2 .text,
#option-3:checked ~ .option-3 .text,
#option-4:checked ~ .option-4 .text{
  color: #fff;
}
.wrapper .box input[type="radio"]{
  display: none;
}

Ahora ha creado con éxito impresionantes botones de radio personalizados usando solo HTML y CSS.

CODE VN

CODE VN

1655734395

Cách tạo các nút radio tùy chỉnh tuyệt vời chỉ sử dụng HTML và CSS

Trong hướng dẫn này, bạn sẽ học cách tạo các Nút radio tùy chỉnh tuyệt vời chỉ bằng HTML và CSS. Để tạo các Nút radio tùy chỉnh tuyệt vời chỉ bằng HTML và CSS. Đầu tiên, bạn cần tạo hai Tệp, một Tệp HTML và một tệp khác là Tệp CSS.

1: Đầu tiên, tạo một tệp HTML với tên là index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Custom Radio Buttons | Codequs</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
  <div class="wrapper">
    <div class="title">Select your option</div>
    <div class="box">
      <input type="radio" name="select" id="option-1">
      <input type="radio" name="select" id="option-2">
      <input type="radio" name="select" id="option-3">
      <input type="radio" name="select" id="option-4">
      <label for="option-1" class="option-1">
        <div class="dot"></div>
        <div class="text">Gamer</div>
      </label>
      <label for="option-2" class="option-2">
        <div class="dot"></div>
        <div class="text">YouTuber</div>
      </label>
      <label for="option-3" class="option-3">
        <div class="dot"></div>
        <div class="text">Student</div>
      </label>
      <label for="option-4" class="option-4">
        <div class="dot"></div>
        <div class="text">Developer</div>
      </label>
    </div>
  </div>

</body>
</html>

2: Thứ hai, tạo một tệp CSS với tên là style.css

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
}
.wrapper{
  width: 350px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 5px 5px 30px rgba(0,0,0,0.2);
}
.wrapper .title{
  color: #fff;
  line-height: 65px;
  text-align: center;
  background: #333;
  font-size: 25px;
  font-weight: 500;
  border-radius: 10px 10px 0 0;
}
.wrapper .box{
  padding: 20px 30px;
  background: #fff;
  border-radius: 10px;
}
.wrapper .box label{
  display: flex;
  height: 53px;
  width: 100%;
  align-items: center;
  border: 1px solid lightgrey;
  border-radius: 50px;
  margin: 10px 0;
  padding-left: 20px;
  cursor: default;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1,
#option-2:checked ~ .option-2,
#option-3:checked ~ .option-3,
#option-4:checked ~ .option-4{
  background: #333;
  border-color: #333;
}
.wrapper .box label .dot{
  height: 20px;
  width: 20px;
  background: #d9d9d9;
  border-radius: 50%;
  position: relative;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot,
#option-2:checked ~ .option-2 .dot,
#option-3:checked ~ .option-3 .dot,
#option-4:checked ~ .option-4 .dot{
  background: #fff;
}
.box label .dot::before{
  position: absolute;
  content: "";
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(2);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot::before,
#option-2:checked ~ .option-2 .dot::before,
#option-3:checked ~ .option-3 .dot::before,
#option-4:checked ~ .option-4 .dot::before{
  background: #333;
  transform: translate(-50%, -50%) scale(1);
}
.wrapper .box label .text{
  color: #333;
  font-size: 18px;
  font-weight: 400;
  padding-left: 10px;
  transition: color 0.3s ease;
}
#option-1:checked ~ .option-1 .text,
#option-2:checked ~ .option-2 .text,
#option-3:checked ~ .option-3 .text,
#option-4:checked ~ .option-4 .text{
  color: #fff;
}
.wrapper .box input[type="radio"]{
  display: none;
}

Bây giờ bạn đã tạo thành công các Nút radio tùy chỉnh tuyệt vời chỉ bằng HTML và CSS.

Как создать потрясающие настраиваемые радиокнопки, используя только HTML и CSS

В этом руководстве вы узнаете, как создавать потрясающие настраиваемые радиокнопки, используя только HTML и CSS. Чтобы создать удивительные пользовательские радиокнопки, используя только HTML и CSS. Во-первых, вам нужно создать два файла: один файл HTML, а другой — файл CSS.

1: Сначала создайте файл HTML с именем index.html.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Custom Radio Buttons | Codequs</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
  <div class="wrapper">
    <div class="title">Select your option</div>
    <div class="box">
      <input type="radio" name="select" id="option-1">
      <input type="radio" name="select" id="option-2">
      <input type="radio" name="select" id="option-3">
      <input type="radio" name="select" id="option-4">
      <label for="option-1" class="option-1">
        <div class="dot"></div>
        <div class="text">Gamer</div>
      </label>
      <label for="option-2" class="option-2">
        <div class="dot"></div>
        <div class="text">YouTuber</div>
      </label>
      <label for="option-3" class="option-3">
        <div class="dot"></div>
        <div class="text">Student</div>
      </label>
      <label for="option-4" class="option-4">
        <div class="dot"></div>
        <div class="text">Developer</div>
      </label>
    </div>
  </div>

</body>
</html>

2: Во-вторых, создайте файл CSS с именем style.css.

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
}
.wrapper{
  width: 350px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 5px 5px 30px rgba(0,0,0,0.2);
}
.wrapper .title{
  color: #fff;
  line-height: 65px;
  text-align: center;
  background: #333;
  font-size: 25px;
  font-weight: 500;
  border-radius: 10px 10px 0 0;
}
.wrapper .box{
  padding: 20px 30px;
  background: #fff;
  border-radius: 10px;
}
.wrapper .box label{
  display: flex;
  height: 53px;
  width: 100%;
  align-items: center;
  border: 1px solid lightgrey;
  border-radius: 50px;
  margin: 10px 0;
  padding-left: 20px;
  cursor: default;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1,
#option-2:checked ~ .option-2,
#option-3:checked ~ .option-3,
#option-4:checked ~ .option-4{
  background: #333;
  border-color: #333;
}
.wrapper .box label .dot{
  height: 20px;
  width: 20px;
  background: #d9d9d9;
  border-radius: 50%;
  position: relative;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot,
#option-2:checked ~ .option-2 .dot,
#option-3:checked ~ .option-3 .dot,
#option-4:checked ~ .option-4 .dot{
  background: #fff;
}
.box label .dot::before{
  position: absolute;
  content: "";
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(2);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot::before,
#option-2:checked ~ .option-2 .dot::before,
#option-3:checked ~ .option-3 .dot::before,
#option-4:checked ~ .option-4 .dot::before{
  background: #333;
  transform: translate(-50%, -50%) scale(1);
}
.wrapper .box label .text{
  color: #333;
  font-size: 18px;
  font-weight: 400;
  padding-left: 10px;
  transition: color 0.3s ease;
}
#option-1:checked ~ .option-1 .text,
#option-2:checked ~ .option-2 .text,
#option-3:checked ~ .option-3 .text,
#option-4:checked ~ .option-4 .text{
  color: #fff;
}
.wrapper .box input[type="radio"]{
  display: none;
}

Теперь вы успешно создали потрясающие настраиваемые радиокнопки, используя только HTML и CSS.

中條 美冬

1655723340

HTMLとCSSのみを使用して素晴らしいカスタムラジオボタンを作成する方法

このガイドでは、HTMLとCSSのみを使用して素晴らしいカスタムラジオボタンを作成する方法を学習します。HTMLとCSSのみを使用して素晴らしいカスタムラジオボタンを作成します。まず、2つのファイルを作成する必要があります。1つはHTMLファイルで、もう1つはCSSファイルです。

1:まず、index.htmlという名前のHTMLファイルを作成します

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Custom Radio Buttons | Codequs</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
  <div class="wrapper">
    <div class="title">Select your option</div>
    <div class="box">
      <input type="radio" name="select" id="option-1">
      <input type="radio" name="select" id="option-2">
      <input type="radio" name="select" id="option-3">
      <input type="radio" name="select" id="option-4">
      <label for="option-1" class="option-1">
        <div class="dot"></div>
        <div class="text">Gamer</div>
      </label>
      <label for="option-2" class="option-2">
        <div class="dot"></div>
        <div class="text">YouTuber</div>
      </label>
      <label for="option-3" class="option-3">
        <div class="dot"></div>
        <div class="text">Student</div>
      </label>
      <label for="option-4" class="option-4">
        <div class="dot"></div>
        <div class="text">Developer</div>
      </label>
    </div>
  </div>

</body>
</html>

2:次に、style.cssという名前のCSSファイルを作成します

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
}
.wrapper{
  width: 350px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 5px 5px 30px rgba(0,0,0,0.2);
}
.wrapper .title{
  color: #fff;
  line-height: 65px;
  text-align: center;
  background: #333;
  font-size: 25px;
  font-weight: 500;
  border-radius: 10px 10px 0 0;
}
.wrapper .box{
  padding: 20px 30px;
  background: #fff;
  border-radius: 10px;
}
.wrapper .box label{
  display: flex;
  height: 53px;
  width: 100%;
  align-items: center;
  border: 1px solid lightgrey;
  border-radius: 50px;
  margin: 10px 0;
  padding-left: 20px;
  cursor: default;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1,
#option-2:checked ~ .option-2,
#option-3:checked ~ .option-3,
#option-4:checked ~ .option-4{
  background: #333;
  border-color: #333;
}
.wrapper .box label .dot{
  height: 20px;
  width: 20px;
  background: #d9d9d9;
  border-radius: 50%;
  position: relative;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot,
#option-2:checked ~ .option-2 .dot,
#option-3:checked ~ .option-3 .dot,
#option-4:checked ~ .option-4 .dot{
  background: #fff;
}
.box label .dot::before{
  position: absolute;
  content: "";
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(2);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot::before,
#option-2:checked ~ .option-2 .dot::before,
#option-3:checked ~ .option-3 .dot::before,
#option-4:checked ~ .option-4 .dot::before{
  background: #333;
  transform: translate(-50%, -50%) scale(1);
}
.wrapper .box label .text{
  color: #333;
  font-size: 18px;
  font-weight: 400;
  padding-left: 10px;
  transition: color 0.3s ease;
}
#option-1:checked ~ .option-1 .text,
#option-2:checked ~ .option-2 .text,
#option-3:checked ~ .option-3 .text,
#option-4:checked ~ .option-4 .text{
  color: #fff;
}
.wrapper .box input[type="radio"]{
  display: none;
}

これで、HTMLとCSSのみを使用して素晴らしいカスタムラジオボタンを正常に作成できました。

Comment créer des boutons radio personnalisés impressionnants en utilisant uniquement HTML et CSS

Dans ce guide, vous apprendrez à créer des boutons radio personnalisés impressionnants en utilisant uniquement HTML et CSS. Pour créer des boutons radio personnalisés impressionnants en utilisant uniquement HTML et CSS. Tout d'abord, vous devez créer deux fichiers, un fichier HTML et un autre fichier CSS.

1 : Tout d'abord, créez un fichier HTML avec le nom de index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Custom Radio Buttons | Codequs</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
  <div class="wrapper">
    <div class="title">Select your option</div>
    <div class="box">
      <input type="radio" name="select" id="option-1">
      <input type="radio" name="select" id="option-2">
      <input type="radio" name="select" id="option-3">
      <input type="radio" name="select" id="option-4">
      <label for="option-1" class="option-1">
        <div class="dot"></div>
        <div class="text">Gamer</div>
      </label>
      <label for="option-2" class="option-2">
        <div class="dot"></div>
        <div class="text">YouTuber</div>
      </label>
      <label for="option-3" class="option-3">
        <div class="dot"></div>
        <div class="text">Student</div>
      </label>
      <label for="option-4" class="option-4">
        <div class="dot"></div>
        <div class="text">Developer</div>
      </label>
    </div>
  </div>

</body>
</html>

2 : Deuxièmement, créez un fichier CSS avec le nom de style.css

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
}
.wrapper{
  width: 350px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 5px 5px 30px rgba(0,0,0,0.2);
}
.wrapper .title{
  color: #fff;
  line-height: 65px;
  text-align: center;
  background: #333;
  font-size: 25px;
  font-weight: 500;
  border-radius: 10px 10px 0 0;
}
.wrapper .box{
  padding: 20px 30px;
  background: #fff;
  border-radius: 10px;
}
.wrapper .box label{
  display: flex;
  height: 53px;
  width: 100%;
  align-items: center;
  border: 1px solid lightgrey;
  border-radius: 50px;
  margin: 10px 0;
  padding-left: 20px;
  cursor: default;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1,
#option-2:checked ~ .option-2,
#option-3:checked ~ .option-3,
#option-4:checked ~ .option-4{
  background: #333;
  border-color: #333;
}
.wrapper .box label .dot{
  height: 20px;
  width: 20px;
  background: #d9d9d9;
  border-radius: 50%;
  position: relative;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot,
#option-2:checked ~ .option-2 .dot,
#option-3:checked ~ .option-3 .dot,
#option-4:checked ~ .option-4 .dot{
  background: #fff;
}
.box label .dot::before{
  position: absolute;
  content: "";
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(2);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  transition: all 0.3s ease;
}
#option-1:checked ~ .option-1 .dot::before,
#option-2:checked ~ .option-2 .dot::before,
#option-3:checked ~ .option-3 .dot::before,
#option-4:checked ~ .option-4 .dot::before{
  background: #333;
  transform: translate(-50%, -50%) scale(1);
}
.wrapper .box label .text{
  color: #333;
  font-size: 18px;
  font-weight: 400;
  padding-left: 10px;
  transition: color 0.3s ease;
}
#option-1:checked ~ .option-1 .text,
#option-2:checked ~ .option-2 .text,
#option-3:checked ~ .option-3 .text,
#option-4:checked ~ .option-4 .text{
  color: #fff;
}
.wrapper .box input[type="radio"]{
  display: none;
}

Vous avez maintenant créé avec succès des boutons radio personnalisés impressionnants en utilisant uniquement HTML et CSS.