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js實現列表類

<script text="text/javascript">
function List()
{
    this.listSize=0;
    this.pos=0;
    this.dataStore=[];
    this.clear=clear;
    this.find=find;
    this.toString=toString;
    this.insert=insert;
    this.append=append;
    this.remove=remove;
    this.front=front;
    this.end=end;
    this.prev=prev;
    this.next=next;
    this.length=length;
    this.currPos=currPos;
    this.moveTo=moveTo;
    this.getElement=getElement;
    this.length=length;
    this.contains=contains;
}
function append(element) 
{
this.dataStore[this.listSize++] = element;
}
function find(element) 
{
    for (var i = 0; i < this.dataStore.length; ++i) 
    {
        if (this.dataStore[i] == element) 
        {
            return i;
        }   
    }
    return -1;
}
function remove(element) 
{
    var foundAt = this.find(element);
    if (foundAt > -1) 
    {
        this.dataStore.splice(foundAt,1);
        --this.listSize;
        return true;
    }
    return false;
}
function length() 
{
    return this.listSize;
}
function toString() 
{
    return this.dataStore;
}
function insert(element, after) 
{
    var insertPos = this.find(after);
    if (insertPos > -1) 
    {
        this.dataStore.splice(insertPos+1, 0, element);
        ++this.listSize;
        return true;
    }
    return false;
}
function clear()
{
    delete this.dataStore;
    this.dataStore = [];
    this.listSize = this.pos = 0;
}
function contains(element) 
{
    for (var i = 0; i < this.dataStore.length; ++i)
    {
        
        if (this.dataStore[i] == element) 
        {
            return true;
        }
    }
    return false;
}
function front() 
{
this.pos = 0;
}
function end() 
{
this.pos = this.listSize-1;
}
function prev() 
{
    if (this.pos > 0) 
    {
        --this.pos;
    }
}
function next() 
{
    if (this.pos < this.listSize-1) 
    {
        ++this.pos;
    }
}
function currPos() 
{
return this.pos;
}
function moveTo(position) 
{
this.pos = position;
}
function getElement() 
{
return this.dataStore[this.pos];
}
function doTest()
{
    var names = new List();
    names.append("Clayton");
    names.append("Raymond");
    names.append("Cynthia");
    names.append("Jennifer");
    names.append("Bryan");
    names.append("Danny");
    names.front();
    document.write(names.getElement());
    names.next();
    document.write(names.getElement());
    names.next();
    names.next();
    names.prev();
    document.write(names.getElement());
}
</script>