我有一个字符串as
string = "firstName:name1, lastName:last1";
现在我需要一个对象obj这样
obj = {firstName:name1, lastName:last1}
我如何在JS中做到这一点?
我有一个字符串as
string = "firstName:name1, lastName:last1";
现在我需要一个对象obj这样
obj = {firstName:name1, lastName:last1}
我如何在JS中做到这一点?
当前回答
由于JSON.parse()方法需要将对象键括在引号中才能正确工作,因此在调用JSON.parse()方法之前,我们首先必须将字符串转换为JSON格式的字符串。
var obj = '{firstName:"John", lastName:"Doe"}'; var jsonStr = obj.replace(/(\w+:)|(\w+:)/g,函数(匹配str) { 返回' ' ' + matchedStr。substring (0, matchedStr。长度- 1)+ '":'; }); obj = JSON.parse(jsonStr);//转换为常规对象 console.log (obj.firstName);//期望输出:John console.log (obj.lastName);//期望输出:Doe
即使字符串有一个复杂的对象(如下所示),这也可以工作,并且仍然可以正确地转换。只要确保字符串本身是用单引号括起来的。
var strorobj = '{名字:"John Doe",年龄:33岁,最爱:{体育:["篮球","棒球"],电影:["星球大战","出租车司机"]}}'; var jsonStr = strObj.replace (/ (\ w +:) | (\ w +:) / g函数(s) { 返回' ' ' + s.substring(0, s.length-1) + ' ' ':'; }); var obj = JSON.parse(jsonStr); console.log (obj.favorites.movies [0]);//期望输出:Star Wars . //
其他回答
实际上,最好的解决方案是使用JSON:
文档
JSON。女孩(文本[一]);
例子:
1)
var myobj = JSON.parse('{ "hello":"world" }');
alert(myobj.hello); // 'world'
2)
var myobj = JSON.parse(JSON.stringify({
hello: "world"
});
alert(myobj.hello); // 'world'
3) 传递一个函数给JSON
var obj = {
hello: "World",
sayHello: (function() {
console.log("I say Hello!");
}).toString()
};
var myobj = JSON.parse(JSON.stringify(obj));
myobj.sayHello = new Function("return ("+myobj.sayHello+")")();
myobj.sayHello();
下面是我处理一些边缘情况的方法,比如将空格和其他基本类型作为值
const str = " c:234 , d:sdfg ,e: true, f:null, g: undefined, h:name ";
const strToObj = str
.trim()
.split(",")
.reduce((acc, item) => {
const [key, val = ""] = item.trim().split(":");
let newVal = val.trim();
if (newVal == "null") {
newVal = null;
} else if (newVal == "undefined") {
newVal = void 0;
} else if (!Number.isNaN(Number(newVal))) {
newVal = Number(newVal);
}else if (newVal == "true" || newVal == "false") {
newVal = Boolean(newVal);
}
return { ...acc, [key.trim()]: newVal };
}, {});
const text = '{"name":"John", "age":30, "city":"New York"}';
const myArr = JSON.parse(text);
document.getElementById("demo").innerHTML = myArr.name;
如果你正在使用JQuery:
var obj = jQuery.parseJSON('{"path":"/img/filename.jpg"}');
console.log(obj.path); // will print /img/filename.jpg
记住:eval是邪恶的!: D
如果你有一个像foo: 1, bar: 2这样的字符串,你可以将它转换为一个有效的obj:
str
.split(',')
.map(x => x.split(':').map(y => y.trim()))
.reduce((a, x) => {
a[x[0]] = x[1];
return a;
}, {});
感谢javascript中的niggler。
更新说明:
const obj = 'foo: 1, bar: 2'
.split(',') // split into ['foo: 1', 'bar: 2']
.map(keyVal => { // go over each keyVal value in that array
return keyVal
.split(':') // split into ['foo', '1'] and on the next loop ['bar', '2']
.map(_ => _.trim()) // loop over each value in each array and make sure it doesn't have trailing whitespace, the _ is irrelavent because i'm too lazy to think of a good var name for this
})
.reduce((accumulator, currentValue) => { // reduce() takes a func and a beginning object, we're making a fresh object
accumulator[currentValue[0]] = currentValue[1]
// accumulator starts at the beginning obj, in our case {}, and "accumulates" values to it
// since reduce() works like map() in the sense it iterates over an array, and it can be chained upon things like map(),
// first time through it would say "okay accumulator, accumulate currentValue[0] (which is 'foo') = currentValue[1] (which is '1')
// so first time reduce runs, it starts with empty object {} and assigns {foo: '1'} to it
// second time through, it "accumulates" {bar: '2'} to it. so now we have {foo: '1', bar: '2'}
return accumulator
}, {}) // when there are no more things in the array to iterate over, it returns the accumulated stuff
console.log(obj)
令人困惑的MDN文档:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce
演示:http://jsbin.com/hiduhijevu/edit?js,控制台
功能:
const str2obj = str => {
return str
.split(',')
.map(keyVal => {
return keyVal
.split(':')
.map(_ => _.trim())
})
.reduce((accumulator, currentValue) => {
accumulator[currentValue[0]] = currentValue[1]
return accumulator
}, {})
}
console.log(str2obj('foo: 1, bar: 2')) // see? works!