How to get it? These p's are all sibling elements. How to get the sequence number of one of these p's?
<p</p>//序号0 <p</p>//序号1 <p</p>//序号2 <p</p>//序号3 <p</p>//序号4
function index(el) { return Array.prototype.indexOf.call(el.parentElement.children, el) }
Read in a loop through the prevSiblings of the element, and read a count+1 until no more is read. The final count is the index
Determine how many nodes there are in front of a certain p, and add one for each additional serial number, until there is no node in front, and then the serial number value of the current node is obtained
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Read in a loop through the prevSiblings of the element, and read a count+1 until no more is read. The final count is the index
Determine how many nodes there are in front of a certain p, and add one for each additional serial number, until there is no node in front, and then the serial number value of the current node is obtained