JS DOM: Show Source Link table

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Function addloadevent (func) {    //does not matter how many functions are executed after the page is loaded  var oldonload  = window.onload;if (typeof window.onload !=  ' function ') {window.onload =  func;} Else{window.onload = function () {oldonload (); func ();}}} Function displaycitations () {//Check compatibility if (!document.getelementsbytagname| |! Document.createelement| |! document.createTextNode)  return false;var quotes = document.getelementsbytagname (" Blockquote "); for ( var i = 0;i < quotes.length; i++) {if (!quotes[i]. GetAttribute ("cite"))  continue;var url = quotes[i].getattribute ("cite");              //gets the value of the cite property: that is, the link var quotechildern =  quotes[i].getelementsbytagname ("*");       //because there is a line break between the P node and the BLOCKQUOTE node, Many browsers will interpret it as several text nodes, so that the LastChild attribute of the BLOCKQUOTE element node//Check whether the length is less than 1&nbsp, and if so, exit this loop immediately.               //is a text node that is not a P element node. The statement is to get the position of the last element node. Recommendation: If not absolutely sure, be sure to check if (quotechildern.length < 1)  continue;                          //lastchild the NodeType property to avoid getting node errors. var elem = quotechildern[quotechildern.length - 1];            var link = document.createelement ("a");     //Create a element Var link_text = document.createtextnode ("source"); Link.appendchild (Link_text); Link.setattribute ("href",  url);           // Add the href attribute to the new link//Insert link var superscript = document.createelement ("Sup");            //sup element: Specifies that the included text is displayed in the form above, usually slightly smaller than the current font. Superscript.appendchild (link);                              //above statement HTML text: <sup><a href= " http://www.w3.org/DOM/">source</a></sup>elem.appendchild (superscript);         //is appended to the last child node of the variable Elem} }addloadevent (displaycitations);

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JS DOM: Show Source Link table