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How to replace an HTML element with another element using JavaScript?

WBOYforward: 2023-09-13 19:37:021546browse

如何使用 JavaScript 将 HTML 元素替换为另一个元素？

In this tutorial, we will learn to replace an HTML element with another element using JavaScript.

In some use cases, we need to replace an entire HTML element with a different element. For example, it is very important in form validation. Suppose we get the user's age from a form, and the user enters the wrong age; we can display a validation message by replacing the HTML element. Another use case where we need to replace an HTML element with another HTML element is dynamic content loading, where we have to display web page content based on certain conditions such as location, etc.

Here, we will learn 3 ways to replace HTML elements on web pages.

Use replaceWith() method

The first method uses the replaceWith() method. We need to execute the replaceWith() method by taking the previous element as a reference and passing a new element as a reference. We can create a new element in string format.

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Users can use the replaceWith() Javascript method to replace one HTML element with another HTML element according to the following syntax.

oldElement.replaceWith(newElement);

In the above syntax, oldElement is a replaceable element and newElement is a replaced element.

Example

In the example below, we have a div element in HTML that contains the id "oldElement". We call the ReplaceElement() function when the button is clicked. In the replaceElement() function, we create a new "h2" element using the createElement() method. Additionally, we use the textContent attribute to add content to the newly created HTML element. After that, we replace oldElement with newElement using replaceWith() method.

In the output, the user can click the button and see the changes on the web page.

<html>
<body>
   <h3> Using the <i> replaceWith() method </i> to replace the HTML elements in JavaScript </h3>
   <div id = "oldElement"> This div is the old element. </div>
   <button onclick = "replaceElement()"> Replace Element </button>
   <script>
      function replaceElement() {
         var newElement = document.createElement('h2');
         newElement.textContent = 'This element is the new element.';
         var oldElement = document.getElementById('oldElement');
         oldElement.replaceWith(newElement);
     }
   </script>
</html>

Use outerHTML attribute

The outerHTML attribute of any element allows us to replace the entire HTML element with another HTML element. We need to assign a new element value to the outerHTML attribute to replace the HTML element.

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Users can use the outerHTML attribute to replace one HTML element with another HTML element according to the following syntax.

document.getElementById(id).outerHTML = newEle;

Example

In the example below, we create a "

" element that contains a "para" id and some text content. In the replaceElement() function, we create a new HTML element in string format and assign its value to the outerHTML attribute of the "

" element.

In the output, the user should click the button to replace the "

" element with the "

" HTML element.

<html>
<body>
   <h3> Using the <i> outerHTML property </i> to replace the HTML elements in JavaScript </h3>
   <p id = "para"> Welcome to the TutorialsPoint! </p>
   <button onclick = "replaceElement()"> Replace Element </button>
   <script>
      function replaceElement() {
         let newEle = '<h2> You clicked the button to replace the element. <h2>';
         document.getElementById('para').outerHTML = newEle;
      }
   </script>
</html>

Example

In the example below, we create a selection menu with different options. Here we will replace the specific options of the selection menu. Additionally, we create two input fields. One is to get the index number, and the other is to get the user's new option value.

In the replaceOption() function, we get the new input value from the user. After that, we access the option using the index value entered by the user in the input. Next, we replace the option with the new value using the option's outerHTML attribute.

In the output, enter the zero-based index value in the first input field, enter the new option value in the second input field, and click the button to replace the option.

<html>
<body>
   <h3> Using the <i> outerHTML property </i> to replace the options in the select menu </h3>
   <label for = "indexInput"> Index: </label>
   <input type = "number" id = "indexInput">  <br>  <br>
   <label for = "valueInput"> New Value: </label>
   <input type = "text" id = "valueInput">   <br>  <br>
   <select id = "demo">
      <option value = "1"> One </option>
      <option value = "2"> Two </option>
      <option value = "3" selected> Three </option>
      <option value = "4"> Four </option>
      <option value = "5"> Five </option>
      <option value = "6"> Six </option>
   </select>
   <button onclick = "replaceOption()"> Replace Option </button>
   <script>
      function replaceOption() {
          // get user input
          var index = parseInt(document.getElementById('indexInput').value);
          var newValue = document.getElementById('valueInput').value;
          var list = document.getElementById('demo');
          // get the option to replace
          var option = list.options[index];
          // replace the option
          option.outerHTML = '<option value="' + newValue + '">' + newValue + '</option>';
      }
   </script>
</html>

Use replaceChild() method

The replaceChild() method allows developers to replace the child nodes of a specific HTML element with a new element. Here we can replace the first child element of a specific element to replace itself with the new element.

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Users can use the replaceChild() method to replace one HTML element with another HTML element according to the following syntax.

oldEle.replaceChild(HTMLele, oldEle.childNodes[0]);

In the above syntax, we need to pass the new element as the first parameter of the replaceChild() method and the old element as the second parameter.

Example

In the following example, first we create the "h3" element using the createElement() method. After that, we use the createTextNode() method to create the text content. After that, we append the text node to the newly created HTML element using the appendChild() method.

Next, we execute the replaceChild() method by referencing the old element. Additionally, we passed HTMLele as the first parameter (a newly created element), and oldEle.childNodes[0] as the second parameter (the first child element of the old element, representing itself).

In the output, click the button and watch the changes on the web page.

<html>
<body>
   <h3> Using the <i> replaceChild() method </i> to replace the HTML elements in JavaScript </h3>
   <p id = "para"> Welcome to the TutorialsPoint! </p>
   <button onclick = "replaceElement()"> Replace Element </button>
   <script>
      function replaceElement() {
         // create a new element
         var HTMLele = document.createElement("h3");
         // create a new text node
         var txt = document.createTextNode("This is a content of new element!");
         // use appendChild() to add a text node to the element
         HTMLele.appendChild(txt);
         var oldEle = document.getElementById("para");
         // using replaceChild() to replace the old element with a new element
         oldEle.replaceChild(HTMLele, oldEle.childNodes[0]);
       }
   </script>
</html>

We learned three different ways to replace one HTML element with another using JavaScript. In the first method, we used the replaceWith() method, which is one of the best and simplest methods. In the second method, we use the outerHTML attribute; in the third method, we use the replaceChild() method, which is generally used to replace child elements.

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How to replace an HTML element with another element using JavaScript?

Use replaceWith() method

grammar

Example

Use outerHTML attribute

grammar

Example

Example

Use replaceChild() method

grammar

Example

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