XML DOM - Remove Nodes

From http://www.w3schools.com (Copyright Refsnes Data)

# XML DOM Remove Nodes

The removeChild() method removes a specified node.

The removeAttribute() method removes a specified attribute.

## Examples

The examples below use the XML file books.xml.
A function, loadXMLDoc(), in an external JavaScript is used to load the XML file.

Remove an element node
This example uses removeChild() to remove the first <book> element.

Remove the current element node
This example uses parentNode and removeChild() to remove the current <book> element.

Remove a text node
This example uses removeChild() to remove the text node from the first <title> element.

Clear the text of a text node
This example uses the nodeValue() property to clear the text node of the first <title> element.

Remove an attribute by name
This example uses removeAttribute() to remove the "category" attribute from the first <book> element.

Remove attributes by object
This example uses removeAttributeNode() to remove all attributes from all <book> elements.

## Remove an Element Node

The removeChild() method removes a specified node.

When a node is removed, all its child nodes are also removed.

The following code fragment will remove the first <book> element from the loaded xml:

    xmlDoc=loadXMLDoc("books.xml");

    y=xmlDoc.getElementsByTagName("book")[0];

    xmlDoc.documentElement.removeChild(y);

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Set the variable y to be the element node to remove
3. Remove the element node by using the removeChild() method from the parent node

Try it yourself

## Remove Myself - Remove the Current Node

The removeChild() method is the only way to removes a specified node.

When you have navigated to the node you want to remove, it is possible to remove that node using the parentNode property and the removeChild() method:

    xmlDoc=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("book")[0];

    x.parentNode.removeChild(x);

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Set the variable y to be the element node to remove
3. Remove the element node by using the parentNode property and the removeChild() method

Try it yourself

## Remove a Text Node

The removeChild() method can also be used to remove a text node:

    xmlDoc=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("title")[0];

    y=x.childNodes[0];
    x.removeChild(y);

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Set the variable x to be the first title element node
3. Set the variable y to be the text node to remove
4. Remove the element node by using the removeChild() method from the parent node

Try it yourself

It is not very common to use removeChild() just to remove the text from a node. The nodeValue property can be used instead. See next paragraph.

## Clear a Text Node

The nodeValue property can be used to change or clear the value of a text node:

    xmlDoc=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("title")[0].childNodes[0];
    x.nodeValue="";

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Set the variable x to be the text node of the first title element
3. Use the nodeValue property to clear the text from the text node

Try it yourself

Loop through and change the text node of all <title> elements: Try it yourself

## Remove an Attribute Node by Name

The removeAttribute(name) method is used to remove an attribute node by its name.

Example: removeAttribute('category')

The following code fragment removes the "category" attribute in the first <book> element:

    xmlDoc=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("book");
    x[0].removeAttribute("category");

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Use getElementsByTagName() to get book nodes
3. Remove the "category" attribute form the first book element node

Try it yourself

Loop through and remove the "category" attribute of all <book> elements: Try it yourself

## Remove Attribute Nodes by Object

The removeAttributeNode(node) method is used to remove an attribute node, using the node object as parameter.

Example: removeAttributeNode(x)

The following code fragment removes all the attributes of all <book> elements:

    xmlDoc=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("book");

    for (i=0;i<x.length;i++)
    {
    while (x[i].attributes.length>0)
      {
      attnode=x[i].attributes[0];
      old_att=x[i].removeAttributeNode(attnode);
      }
    }

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Use getElementsByTagName() to get all book nodes
3. For each book element check if there are any attributes
4. While there are attributes in a book element, remove the attribute

Try it yourself

From http://www.w3schools.com (Copyright Refsnes Data)