js判斷樣式className同時增加class或刪除class_javascript技巧

複製程式碼 程式碼如下:

function MyClass () {}
MyClass.hasClassName = MyClass.hasClassName =MyClass.hasClassName. element, className)
{
if (!element) return;
var elementClassName = element.className;
if (elementClassName.length == 0) return false;
if (elementClassName.length == 0) return false;
//用正則表達式判斷多個class之間是否存在真正的class（前後空格的處理）
if (elementClassName == className || elementClassName.match(new RegExp("(^|\s)" className "(\s |$)")))
return true;
return false;
};
MyClass.addClassName = function(element, className)
{
if (!element) return ;
var elementClassName = element.className;
if (elementClassName.length == 0)
{
element.className = elementClassName;
return;
}
if (ClassName;
return;
}
if (ClassName;
return; }
if elementClassName == className || elementClassName.match(new RegExp("(^|\s)" className "(\s|$)")))
return;
element.className = elementClassName " " className;
};
MyClass.removeClassName = function(element, className)
{
if (!element) return;
var elementClassName = element.className;
if == 0) return;
if(elementClassName == className)
{
element.className = "";

return; } if (elementClassName.match(new RegExp ("(^|\s)" className "(\s|$)"))) element.className = elementClassName.replace((new RegExp("(^|\s)" className "(\s| $)"))," "); };