/*字典 Dictionary类*/
function Dictionary() {
this.add = add;
this.datastore = new Array();
this.find = find;
this.remove = remove;
this.showAll = showAll;
this.count = count;
this.clear = clear;
}
function add(key, value) {
this.datastore[key] = value;
}
function find(key) {
return this.datastore[key];
}
function remove(key) {
delete this.datastore[key];
}
function showAll() {
var str = "";
for(var key in this.datastore) {
str += key + " -> " + this.datastore[key] + "; "
}
console.log(str);
}
function count() {
/*var ss = Object.keys(this.datastore).length;
console.log("ssss "+ss);
return Object.keys(this.datastore).length;*/
/**/
var n = 0;
for(var key in Object.keys(this.datastore)) {
++n;
}
console.log(n);
return n;
}
function clear() {
for(var key in this.datastore) {
delete this.datastore[key];
}
}
var pbook = new Dictionary();
pbook.add("Mike", "723");
pbook.add("Jennifer", "987");
pbook.add("Jonathan", "666");
pbook.showAll();//Mike -> 723; Jennifer -> 987; Jonathan -> 666;
pbook.count();//3
pbook.remove("Jennifer");
//pbook.clear();
pbook.showAll();//Mike -> 723; Jonathan -> 666;
pbook.count();//2
