【www.bbyears.com--正则表达式】
通常先使用getElementsByTagName("*")取出文档中所有元素，然后进行遍历，使用正则表达式找出匹配的元素放入一个数组返回。由于IE5不支持document.getElementsByTagName("*")，要使用分支document.all以防错误
下面的方法完美支持了document写法
代码如下if(!document.getElementsByClassName){
document.getElementsByClassName = function(className, element){
var children = (element || document).getElementsByTagName("*");
var elements = new Array();
for (var i=0; i
var classNames = child.className.split(" ");
for (var j=0; j
elements.push(child);
break;
}
}
}
return elements;
};
}
最最终的方案为：
代码如下var getElementsByClassName = function (searchClass, node,tag) {
if(document.getElementsByClassName){
var nodes = (node || document).getElementsByClassName(searchClass),result = [];
for(var i=0 ;node = nodes[i++];){
if(tag !== "*" && node.tagName === tag.toUpperCase()){
result.push(node)
}else{
result.push(node)
}
}
return result
}else{
node = node || document;
tag = tag || "*";
var classes = searchClass.split(" "),
elements = (tag === "*" && node.all)? node.all : node.getElementsByTagName(tag),
patterns = [],
current,
match;
var i = classes.length;
while(--i >= 0){
patterns.push(new RegExp("(^|\s)" + classes[i] + "(\s|$)"));
}
var j = elements.length;
while(--j >= 0){
current = elements[j];
match = false;
for(var k=0, kl=patterns.length; k
if (!match) break;
}
if (match) result.push(current);
}
return result;
}
}