NodeFilter.acceptNode() - Web APIs 编辑

The NodeFilter.acceptNode() method returns an unsigned short that will be used to tell if a given Node must be accepted or not by the NodeIterator or TreeWalker iteration algorithm. This method is expected to be written by the user of a NodeFilter. Possible return values are:

The function should return NodeFilter.FILTER_ACCEPT, which causes the TreeWalker to return the node, NodeFilter.FILTER_REJECT, which causes the TreeWalker to ignore the entire subtree, or NodeFilter.FILTER_SKIP.

The browser doesn't provide any object implementing this method. It is the user who is expected to write an object implementing the NodeFilter interface, tailoring the acceptNode() method to its needs, and using it with some TreeWalker or NodeIterator objects.

Syntax

result = nodeFilter.acceptNode(node)

Parameters

node

Is a Node being the object to check against the filter.

Example

var nodeIterator = document.createNodeIterator(
  // Node to use as root
  document.getElementById('someId'),

  // Only consider nodes that are text nodes (nodeType 3)
  NodeFilter.SHOW_TEXT,

  // Object containing the function to use for the acceptNode method
  // of the NodeFilter
    { acceptNode: function(node) {
      // Logic to determine whether to accept, reject or skip node
      // In this case, only accept nodes that have content
      // other than whitespace
      if ( ! /^\s*$/.test(node.data) ) {
        return NodeFilter.FILTER_ACCEPT;
      }
    }
  },
  false
);

// Show the content of every non-empty text node that is a child of root
var node;

while ((node = iterator.nextNode())) {
  alert(node.data);
}

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• The interface it belongs to: NodeFilter.