How to dynamically add style rules in Javascript depth

You can add CSS in the following ways: inline, embedded, external chained, and imported. A. dynamically introduces the style sheet file: function loadlink (URL) {var link = document. createelement ("Link"); Link. type = "text/CSS"; Link. rel = "stylesheet"; Link. href = URL; var head = document. getelmentsbytagname ("head") [0]; head. appendchild (Link);} B) embedded: function insertstyles () {var doc, csscode = [], csstext; var Len = arguments. length; var head, style, firststyle; If (LEN = 1) {Doc = Document; csscode. push (arguments [0 ])} Else if (LEN = 2) {Doc = arguments [0]; csscode. push (arguments [1]);} else {alert ("the function can receive up to two parameters! ");} Head = Doc. getelementsbytagname ("head") [0]; styles = head. getelementsbytagname ("style"); If (styles. length = 0) {If (Doc. createstylesheet) {// iedoc. createstylesheet ();} else {// ffvar tempstyle = Doc. createelement ("style"); tempstyle. setattibute ("type", text/CSS "); head. appendchild (tempstyle) ;}} firststyle = styles [0]; csstext = csscode. join ("\ n"); If (! + "\ V1") {// opacity compatible with var str = csstext. Match (/opacity :( \ D? \. \ D +);/); If (STR! = NULL) {csstext = csstext. replace (STR [0], "filter: alpha (opacity =" + parefloat (STR [1]) * 100 + ")" plain text + = csstext ;} else if (Doc. getboxobjectfor) {firststyle. innerhtml + = csstext;} else {firststyle. appendchild (Doc. createtextnode (csstext);} C) in-row formula: var addstyle = function (Ele, STR) {var S = ELE. getattribute ("style"), styles; If (STR & typeof STR = "string") {If (! Ssf-cancele.style.css text = STR;} else {If (S = '[ object] ') {// IE6/7 E. getattribute ("style" returns [objectobject]s=ele.style.css text;} styles = trim (s ). split (";"); For (VAR I = 0, Len = styles. length; I <Len; I ++) {var style_ I = trim (styles [I]); var ATTR = style_ I .split (":") [0]; If (Str. indexof (ATTR)>-1) {styles [I] = "" ;}else{styles[ I ]=style_ile}}ele.style.css text = styles. join ("") + ";" + STR ;}} d) Import: Import "index.css"; methods related to CSS operations: var hasc Lass = function (Ele, value) {var rclass =/[\ n \ t \ r]/g, value = "" + value + ""; Return (Ele. nodetype = 1) & ("" + ELE. classname + ""). replace (rclass ,""). indexof (value)>-1;} var trim = function (VAL) {return Val. replace (/(^ \ s +) | (\ s + $)/g, "");} var addclass = function (Ele, value) {var rspace =/\ s +/, classnames, getclass; If (Value & typeof value = "string") {classnames = value. split (rspace); If (Ele. nodetype = 1) {If (! Ele. classname & classnames. length = 1) {ELE. classname = value;} else {getclass = "" + ELE. classname + ""; for (VAR I = 0, Len = classnames. length; I <Len; I ++) {var cname = classnames [I]; If (! Hasclass (Ele, cname) {getclass + = cname + "" ;}} ELE. classname = trim (getclass) ;}}} var removeclass = function (Ele, value) {var rclass =/[\ n \ t \ r]/g, classnames, getclass; if (Value & typeof value = "string") | value = undefined) {classnames = (value | ""). split (rspace); If (Ele. nodetype = 1 & ELE. classname) {If (value) {// There is a search for the class to be removed getclass = "" + ELE. classname + "". replace (rclass, ""); // left and right spaces. To ensure equality among classes, replace for (VAR I = 0, Len = classnames. length; I <Len; I ++) {getclass = getclass. replace ("" + classnames [I] + "", "")} ELE. classname = trim (getclass);} else {// remove all classes ELE. classname = "" ;}}} var toggleclass = function (Ele, value) {If (typeof value = "string") {If (hasclass (Ele, value )) {removeclass (Ele, value) ;}else {addclass (Ele, value );}}}