怎么才能讓a的部分?jǐn)?shù)據(jù)發(fā)生變化，而不是重新把整個(gè)新的JSON數(shù)據(jù)賦值給a？

a.filter(item => item['省會(huì)'] === '杭州123')[0]['金額'] = 55;

let arr = a.filter(ele => ele['省會(huì)'] == '香22港3');
for(let val of arr){
    val['金額'] = '123.45';
}

a.map(ele => {
    if (ele['省會(huì)'] !== '北京123') return;
    ele['金額'] = 123.45;
})

var a1 = ['a', 10, 'b', 20, 'c', 30];
var a2 = a1.filter(function(item) {
    return typeof item == 'number';
});
console.log(a2);

let a = [
    {
        "省會(huì)": "北京123",
        "金額": 29097061.66
    },
    {
        "省會(huì)": "廣州123",
        "金額": 19784491.69
    },
    {
        "省會(huì)": "杭州123",
        "金額": 14068375.59
    },
    {
        "省會(huì)": "南1京1",
        "金額": 13391405.93
    },
    {
        "省會(huì)": "香22港3",
        "金額": 11244012.29
    },
    {
        "省會(huì)": "香22港3",
        "金額": 11244012.29
    },
    {
        "省會(huì)": "香22港3",
        "金額": 11244012.29
    }
]

var c = a.filter(function (item) {
    return item['省會(huì)'] === '杭州123';
});

console.log(c);
console.log(c[0]);

let ar = new Array();
ar = ['d','v','q']
console.log(ar[1]);

a.filter(item => item['省會(huì)'] === '杭州123')[0]['金額'] = 55;

console.log(a)

a.filter(item => item['省會(huì)'] === '杭州123')[0]['金額'] = 55;

a.filter(function (item) {
  return item['省會(huì)'] === '杭州123';
})[0]['金額'] = 55;