使用JSON解析/stringify操作数据

Manipulating data using JSON parse/stringify

本文关键字:操作 操作数 数据 stringify JSON 解析 使用      更新时间:2023-09-26

我有一个关于使用Javascript和stringify/parse操作JSON数据的问题。在下面的示例中,我创建了一个JSON字符串,然后使用parse将其转换回对象。完成此操作后,我想做的是删除具有特定ID的项,而我能找到的唯一方法是遍历整个数组,并在找到匹配项后从数组中删除元素。这似乎不是很有效。有更好的方法吗?

var employees = [];
//build the array
for (var i=0; i < 10; i++) {
    var player = { "id": i, "salary": i*1000000 };
    employees.push(player);
}
json_employees = JSON.stringify({employees: employees}); //convert to json string
alert(json_employees); //display the new string
var obj = JSON.parse(json_employees); //convert back to a Javascript object
for (var j=0; j < obj.employees.length; j++) { // loop through the array
    if (obj.employees[j].id === 5) // is it the employee with id 5?
        obj.employees.splice(j, 1); // remove the fifth item
}
json_modified_employees = JSON.stringify({employees: obj.employees}); //convert back to json string
alert(json_modified_employees); //display the new string

您可以将员工存储在一个对象中,其中包含他们的id密钥,类似于以下内容:

// create a store object
var employees = {};
//build the array
for (var i=0; i < 10; i++) {
    var player = { "id": i, "salary": i*1000000 };
    // add item to store object with a key of 'pk' + i
    employees['pk' + i] = player;
}
json_employees = JSON.stringify({employees: employees}); //convert to json string
alert(json_employees); //display the new string
var obj = JSON.parse(json_employees); //convert back to a Javascript object
// remove the required item (in this case number 5)
delete obj.employees['pk' + 5];
json_modified_employees = JSON.stringify({employees: obj.employees}); //convert back to json string
alert(json_modified_employees); //display the new string

如果你想迭代你的员工,你会

for (var key in employees) {
    if (employees.hasOwnProperty(key)) {
        alert(employees[key].id)
    }
}