js html elements dom cheet sheet

HTML
// grab element on page you want to add stuff to
var firstHeading = document.getElementById('firstHeading');

// add both new elements to the page as children to the element we stored in firstHeading.
firstHeading.appendChild(newHeading);
firstHeading.appendChild(newParagraph);

// can also insert before like so

// get parent node of firstHeading
var parent = firstHeading.parentNode;

// insert newHeading before FirstHeading
parent.insertBefore(newHeading, firstHeading);// Get child nodes
var stored = document.getElementById('someid');
var children = stored.childNodes;

// Get parent node
var parental = children.parentNode;// create new elments
var newHeading = document.createElement('h1');
var newParagraph = document.createElement('p');

// create text nodes for new elements
var h1Text= document.createTextNode('This is a nice header text!');
var pText= document.createTextNode('This is a nice paragraph text!');

// attach new text nodes to new elements
newHeading.appendChild(h1Text);
newParagraph.appendChild(pText);

// elements are now created and ready to be added to the DOM.// Returns a reference to the element by its ID.
document.getElementById('someid');

// Returns an array-like object of all child elements which have all of the given class names.
document.getElementsByClassName('someclass');

// Returns an HTMLCollection of elements with the given tag name.
document.getElementsByTagName('LI');

// Returns the first element within the document that matches the specified group of selectors.
document.querySelector('.someclass');

// Returns a list of the elements within the document (using depth-first pre-order traversal of the document's nodes)
// that match the specified group of selectors.
document.querySelectorAll('div.note, div.alert');
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