Implement prepend and append with regular JavaScript

The task is to implement prepend() and append() method using regular JavaScript. We’re going to discuss a few methods.
First few methods to know

insertBefore() Method:
This method inserts a node as a child, just before an existing child, which is specified.

Syntax:
```
node.insertBefore(newNode, existingNode)
```
Parameters:
- newNode: This parameter is required. It specifies the node object to insert.
- existingNode: This parameter is required. It specifies the child node to insert the new node before it. If not used, the method will insert the newNode at the end.
Return value:
It returns a node object, which represents the inserted node.
appendChild() Method:
This method appends a node as the last child of a node.
Syntax:
```
node.appendChild(Node)
```
Parameters:
- Node: This parameter is required. It specifies the node object to append.
Return value:
It returns a node object, Which represents the appended node.

Example 1: This example creates a new <p> element and inserts it as the first child of the <div> element using insertBefore() method.

<!DOCTYPE HTML> 
<html> 
  
<head> 
    <title> 
        JavaScript  
      | implement prepend and  
      append with regular JavaScript. 
    </title> 
</head> 
  
<body style="text-align:center;" id="body"> 
    <h1 style="color:green;">   
            GeeksForGeeks   
        </h1> 
    <p id="GFG_UP" 
       style="font-size: 15px; font-weight: bold;"> 
    </p> 
    <div id="parent"> 
        <p class="child">child_1</p> 
        <p class="child">child_2</p> 
        <p class="child">child_3</p> 
    </div> 
    <button onclick="gfg_Run()"> 
        Click here 
    </button> 
    <p id="GFG_DOWN"
       style="color:green;  
              font-size: 20px; 
              font-weight: bold;"> 
    </p> 
    <script> 
        var el_up = document.getElementById("GFG_UP"); 
        var el_down = document.getElementById("GFG_DOWN"); 
        var today = 'Click on button implement prepend method'; 
        el_up.innerHTML = today; 
  
        function gfg_Run() { 
            var par = document.getElementById("parent"); 
            var child = document.getElementsByClassName("child"); 
            var newEl = document.createElement("p"); 
            newEl.innerHTML = "child_0"; 
            par.insertBefore(newEl, child[0]); 
            el_down.innerHTML = "New element inserted"; 
        } 
    </script> 
</body> 
  
</html> 

Output:

Before clicking on the button:
After clicking on the button:

Example 2: This example creates a new <p> element and inserts it as the last child of the <div> element using appendChild() method.

<!DOCTYPE HTML> 
<html> 
  
<head> 
    <title> 
        JavaScript  
      | implement prepend and append  
      with regular JavaScript. 
    </title> 
</head> 
  
<body style="text-align:center;" id="body"> 
    <h1 style="color:green;">   
            GeeksForGeeks   
        </h1> 
    <p id="GFG_UP"
       style="font-size: 15px; 
              font-weight: bold;"> 
    </p> 
    <div id="parent"> 
        <p class="child">child_1</p> 
        <p class="child">child_2</p> 
        <p class="child">child_3</p> 
    </div> 
    <button onclick="gfg_Run()"> 
        Click here 
    </button> 
    <p id="GFG_DOWN"
       style="color:green;  
              font-size: 20px; 
              font-weight: bold;"> 
    </p> 
    <script> 
        var el_up = document.getElementById("GFG_UP"); 
        var el_down = document.getElementById("GFG_DOWN"); 
        var today = 'Click on button implement append method'; 
        el_up.innerHTML = today; 
  
        function gfg_Run() { 
            var par = document.getElementById("parent"); 
            var newEl = document.createElement("p"); 
            newEl.innerHTML = "child_4"; 
            par.appendChild(newEl); 
            el_down.innerHTML = "New element inserted"; 
        } 
    </script> 
</body> 
  
</html> 

Output:

Before clicking on the button:
After clicking on the button:

My Personal Notes

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