使用 Javascript 更新 JSON 对象
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Updating a JSON object using Javascript
提问by Abishek
How can i update the following JSON object dynamically using javascript or Jquery?
如何使用 javascript 或 Jquery 动态更新以下 JSON 对象？
var jsonObj = [{'Id':'1','Username':'Ray','FatherName':'Thompson'},
{'Id':'2','Username':'Steve','FatherName':'Johnson'},
{'Id':'3','Username':'Albert','FatherName':'Einstein'}]
I would like to dynamically update the Username to 'Thomas' where the 'Id' is '3'.
我想将用户名动态更新为“Thomas”，其中“Id”为“3”。
How can I acheive this?
我怎样才能做到这一点？
回答by Michael Berkowski
A plain JavaScript solution, assuming jsonObjalready contains JSON:
一个普通的 JavaScript 解决方案，假设jsonObj已经包含 JSON：
Loop over it looking for the matching Id, set the corresponding Username, and breakfrom the loop after the matched item has been modified:
遍历它寻找匹配的Id，设置相应的用户名，并break在匹配项被修改后从循环中：
for (var i = 0; i < jsonObj.length; i++) {
if (jsonObj[i].Id === 3) {
jsonObj[i].Username = "Thomas";
break;
}
}
Here's the same thing wrapped in a function:
这是封装在函数中的相同内容：
function setUsername(id, newUsername) {
for (var i = 0; i < jsonObj.length; i++) {
if (jsonObj[i].Id === id) {
jsonObj[i].Username = newUsername;
return;
}
}
}
// Call as
setUsername(3, "Thomas");
回答by qiao
simply iterate over the list then check the properties of each object.
只需遍历列表然后检查每个对象的属性。
for (var i = 0; i < jsonObj.length; ++i) {
if (jsonObj[i]['Id'] === '3') {
jsonObj[i]['Username'] = 'Thomas';
}
}
回答by Vignesh Rajendran
$(document).ready(function(){
var jsonObj = [{'Id':'1','Username':'Ray','FatherName':'Thompson'},
{'Id':'2','Username':'Steve','FatherName':'Johnson'},
{'Id':'3','Username':'Albert','FatherName':'Einstein'}];
$.each(jsonObj,function(i,v){
if (v.Id == 3) {
v.Username = "Thomas";
return false;
}
});
alert("New Username: " + jsonObj[2].Username);
});
回答by Joe Johnston
I took Michael Berkowski's answer a step (or two) farther and created a more flexible function allowing any lookup field and any target field. For fun I threw splat (*) capability in there incase someone might want to do a replace all. jQuery is NOT needed.checkAllRows allows the option to break from the search on found for performance or the previously mentioned replace all.
我将Michael Berkowski的回答更进一步（或两步），并创建了一个更灵活的函数，允许任何查找字段和任何目标字段。为了好玩，我在那里扔了 splat (*) 功能，以防有人可能想要全部替换。不需要 jQuery。checkAllRows 允许选择中断搜索以提高性能或前面提到的全部替换。
function setVal(update) {
/* Included to show an option if you care to use jQuery
var defaults = { jsonRS: null, lookupField: null, lookupKey: null,
targetField: null, targetData: null, checkAllRows: false };
//update = $.extend({}, defaults, update); */
for (var i = 0; i < update.jsonRS.length; i++) {
if (update.jsonRS[i][update.lookupField] === update.lookupKey || update.lookupKey === '*') {
update.jsonRS[i][update.targetField] = update.targetData;
if (!update.checkAllRows) { return; }
}
}
}
var jsonObj = [{'Id':'1','Username':'Ray','FatherName':'Thompson'},
{'Id':'2','Username':'Steve','FatherName':'Johnson'},
{'Id':'3','Username':'Albert','FatherName':'Einstein'}]
With your data you would use like:
使用您的数据，您将使用：
var update = {
jsonRS: jsonObj,
lookupField: "Id",
lookupKey: 2,
targetField: "Username",
targetData: "Thomas",
checkAllRows: false
};
setVal(update);
And Bob's your Uncle. :) [Works great]
而鲍勃是你的叔叔。:) [效果很好]
回答by Rodik
use:
用：
var parsedobj = jQuery.parseJSON( jsonObj);
This will only be useful if you don't need the format to stay in string. otherwise you'd have to convert this back to JSON using the JSON library.
这仅在您不需要将格式保留在字符串中时才有用。否则，您必须使用 JSON 库将其转换回 JSON。
回答by Zirak
var i = jsonObj.length;
while ( i --> 0 ) {
if ( jsonObj[i].Id === 3 ) {
jsonObj[ i ].Username = 'Thomas';
break;
}
}
Or, if the array is always ordered by the IDs:
或者，如果数组始终按 ID 排序：
jsonObj[ 2 ].Username = 'Thomas';
回答by Drew Noakes
JSON is the JavaScript Object Notation. There is no such thing as a JSON object. JSON is just a way of representing a JavaScript object in text.
JSON 是 JavaScript对象表示法。没有JSON 对象这样的东西。JSON 只是一种用文本表示 JavaScript 对象的方式。
So what you're after is a way of updating a in in-memory JavaScript object. qiao's answershows how to do that simply enough.
因此，您所追求的是一种更新内存中 JavaScript 对象的方法。 乔的回答显示了如何简单地做到这一点。
回答by Musa
For example I am using this technique in Basket functionality.
例如，我在篮子功能中使用这种技术。
Let us add new Item to Basket.
让我们向 Basket 添加新项目。
var productArray=[];
$(document).on('click','[cartBtn]',function(e){
e.preventDefault();
$(this).html('<i class="fa fa-check"></i>Added to cart');
console.log('Item added ');
var productJSON={"id":$(this).attr('pr_id'), "nameEn":$(this).attr('pr_name_en'), "price":$(this).attr('pr_price'), "image":$(this).attr('pr_image'), "quantity":1, "discount":0, "total":$(this).attr('pr_price')};
if(localStorage.getObj('product')!==null){
productArray=localStorage.getObj('product');
productArray.push(productJSON);
localStorage.setObj('product', productArray);
}
else{
productArray.push(productJSON);
localStorage.setObj('product', productArray);
}
itemCountInCart(productArray.length);
});
After adding some item to basket - generates json array like this
将一些项目添加到篮子后 - 生成这样的 json 数组
[
{
"id": "95",
"nameEn": "New Braslet",
"price": "8776",
"image": "1462012394815.jpeg",
"quantity": 1,
"discount": 0,
"total": "8776"
},
{
"id": "96",
"nameEn": "new braslet",
"price": "76",
"image": "1462012431497.jpeg",
"quantity": 1,
"discount": 0,
"total": "76"
},
{
"id": "97",
"nameEn": "khjk",
"price": "87",
"image": "1462012483421.jpeg",
"quantity": 1,
"discount": 0,
"total": "87"
}
]
For Removing some item from Basket.
用于从篮子中取出某些物品。
$(document).on('click','[itemRemoveBtn]',function(){
var arrayFromLocal=localStorage.getObj('product');
findAndRemove(arrayFromLocal,"id",$(this).attr('basketproductid'));
localStorage.setObj('product', arrayFromLocal);
loadBasketFromLocalStorageAndRender();
});
//This function will remove element by specified property. In my case this is ID.
function findAndRemove(array, property, value) {
array.forEach(function(result, index) {
if(result[property] === value) {
//Remove from array
console.log('Removed from index is '+index+' result is '+JSON.stringify(result));
array.splice(index, 1);
}
});
}
And Finally the real answer of the question "Updating a JSON object using JS". In my example updating product quantity and total price on changing the "number" element value.
最后是“使用 JS 更新 JSON 对象”问题的真正答案。在我的示例中，通过更改“数字”元素值来更新产品数量和总价。
$(document).on('keyup mouseup','input[type=number]',function(){
var arrayFromLocal=localStorage.getObj('product');
setQuantityAndTotalPrice(arrayFromLocal,$(this).attr('updateItemid'),$(this).val());
localStorage.setObj('product', arrayFromLocal);
loadBasketFromLocalStorageAndRender();
});
function setQuantityAndTotalPrice(array,id,quantity) {
array.forEach(function(result, index) {
if(result.id === id) {
result.quantity=quantity;
result.total=(quantity*result.price);
}
});
}
回答by mahendren
var jsonObj = [{'Id':'1','Quantity':'2','Done':'0','state':'todo',
'product_id':[315,"[LBI-W-SL-3-AG-TA004-C650-36] LAURA BONELLI-WOMEN'S-SANDAL"],
'Username':'Ray','FatherName':'Thompson'},
{'Id':'2','Quantity':'2','Done':'0','state':'todo',
'product_id':[314,"[LBI-W-SL-3-AG-TA004-C650-36] LAURA BONELLI-WOMEN'S-SANDAL"],
'Username':'Steve','FatherName':'Johnson'},
{'Id':'3','Quantity':'2','Done':'0','state':'todo',
'product_id':[316,"[LBI-W-SL-3-AG-TA004-C650-36] LAURA BONELLI-WOMEN'S-SANDAL"],
'Username':'Albert','FatherName':'Einstein'}];
for (var i = 0; i < jsonObj.length; ++i) {
if (jsonObj[i]['product_id'][0] === 314) {
this.onemorecartonsamenumber();
jsonObj[i]['Done'] = ""+this.quantity_done+"";
if(jsonObj[i]['Quantity'] === jsonObj[i]['Done']){
console.log('both are equal');
jsonObj[i]['state'] = 'packed';
}else{
console.log('not equal');
jsonObj[i]['state'] = 'todo';
}
console.log('quantiy',jsonObj[i]['Quantity']);
console.log('done',jsonObj[i]['Done']);
}
}
console.log('final',jsonObj);
}
quantity_done: any = 0;
onemorecartonsamenumber() {
this.quantity_done += 1;
console.log(this.quantity_done + 1);
}
