1.List list = new ArrayList。
2.list.add(测试1)。
3.list.add(测试2)。
4.list.add(测试3)。
5.JSONArray jsonArray JSONArray.fromObject(list)。
6.System.out.println(jsonArray.toString。
7.这边要导包需要jsonlib.jarnet.sf.json.JSONArray。
用java初始化一个list,向list中添加值,并输出list中的值:
1.import java.util.
2.public class .
3. public static void main(String arg[]) .
4. List lis = new Arraylist.
5. lis.add("wo").
6. lis.add("shi").
7. lis.add("wang").
8.for(int i=0i<lis.size()i++).
9. System.out.print(lis.get(i)+"").
1、方法思路使用js数组自带的filter()方法；数据格式要求，父子节点通过，Id，ParentId进行关联。默认父结节id为0。
样例数据：var jsonData = [{"id":"1","pid":"0","name":"家用电器"}, {"id":"4","pid":"1","name":"大家电"}, {"id":"5","pid":"1","name":"生活电器"}, {"id":"2","pid":"0","name":"服饰"}, {"id":"3","pid":"0","name":"化妆"}, {"id":"7","pid":"4","name":"空调"}, {"id":"8","pid":"4","name":"冰箱"}, {"id":"9","pid":"4","name":"洗衣机"}, {"id":"10","pid":"4","name":"热水器"}, {"id":"11","pid":"3","name":"面部护理"}, {"id":"12","pid":"3","name":"口腔护理"}, {"id":"13","pid":"2","name":"男装"}, {"id":"14","pid":"2","name":"女装"}, {"id":"15","pid":"7","name":"海尔空调"}, {"id":"16","pid":"7","name":"美的空调"}, {"id":"19","pid":"5","name":"加湿器"}, {"id":"20","pid":"5","name":"电熨斗"}]
2、实现方法：
function creatTreeData(list){
var clonelist = JSON.parse(JSON.stringify(list))
var result =clonelist.filter(function(father){
var childlist = clonelist.filter(function(child){
return father.id= child.pid
})
if(childlist.length>0){
father.children=childlist
}
return father.pid ==0
})
return result
}
3、方法封装
function treeData(list,id,pid,children){
var clone = JSON.parse(JSON.stringify(list))
return clone.filter(function(father){
var childlist =clone.filter(function(child){
return father[id]==child[pid]
})
if(childlist.length>0){
father[children]=childlist
}
return father[pid]==0
})
}
js对象转json数据: JOSN.stringify()
json数据转js对象: JSON.parse()
<script>var obj = {
a : 'A',
b : 'B',
c : 'C'
}
var json = JSON.stringify(obj)
console.log(json)
console.log(typeof json)
console.log('--------------------------')
var obj2 = JSON.parse(json)
console.log(obj2)
console.log(typeof obj2)
</script>
