The difference _javascript skills between childnodes.length and Children.length

BecausechildnodesContains more than justHTMLNodeAllProperty，Text, etc. are included in thechildnodesInside,You can passNodeTypeTo determine what type of node it is, only whennodetype==1To make the element node,2is the attribute node,3is a text node. and Children.length only the number of nodes is counted.
This includes the calculation of the node length, which should be noted when the node is moved.
To get the text of an element, such as to get aPThe text of the node, some people like to useInnerHTML, the change is the same, in fact this is not very good, because the use ofInnerHTMLThe browser will think that what you are inserting is a piece of label text, and you just want to insert a piece of plain text, which causes the browser to try to parse your plain text, which can cause unnecessary waste of resources. So it is recommended to useElement.firstChild.nodeValue,Why isFirstChildIt? BecauseChildnodes[0]is the text node, you can look at it without believing it.NodeType