js數據格式和json數據格式,各有各的用處,就我的而言,json更好用一點,js自身的數組和對像限制比較多。json
以js的數組舉例:
查看複製打印?
var a = ['1'];
a[5] = 52;
a.length //這兒的結果是6,也就是說,中間的key會自動補全,而值呢,是undefined 。數組
一,添加和刪除
1,一維數組
查看複製打印?
test = {}; //空json對像
test['firstname'] = "tank"; //添加二個元素
test['lastname'] = "zhang";
console.log(test); //查看
delete test['lastname']; //刪除json中的某個元素
console.log(test); 排序
2,二維數組
查看複製打印?
test1 = [{"name":"tank","total":"100"},{"name":"zhang","total":"23"},{"name":"hao","total":"325"}];
add = {"name":"may"};
test1.push(add); //添加一個元素
console.log(test1);
delete test1[2]; //刪除一個元素
console.log(test1); io
二,排序
1,一維數組
查看複製打印?
test = ["100","23","325"]; //定義個數組
function sortNumber(a,b) //定義排序方法
{
return a - b
}
test1_sort=test.sort(sortNumber);
console.log(test1_sort); console
2,二維數組
查看複製打印?
test1 = [{"name":"tank","total":"100"},{"name":"zhang","total":"23"},{"name":"hao","total":"325"}];
sort_by = function(field, reverse, primer){ //定義排序方法
var key = primer ?
function(x) {return primer(x[field])} :
function(x) {return x[field]};
reverse = [-1, 1][+!!reverse];
return function (a, b) {
return a = key(a), b = key(b), reverse * ((a > b) - (b > a));
}
}
test1_sort=test1.sort(sort_by('total', true, parseInt)); //根據total,升序排
console.log(test1_sort);
test1_sort=test1.sort(sort_by('name', false, '')); //根據name,倒序排
console.log(test1_sort); ast
別看是小問題,可是若是長時間不用,也會生疏,或者忘了。