如何将字符串 {} 值替换为 obj（键值）

Question

I recently started programming on nodeJs.

I have different strings and Json Object;

eg :

var str = 'My name is {name} and my age is {age}.';
var obj = {name : 'xyz' , age: 24};


var str = 'I live in {city} and my phone number is {number}.';
var obj = {city: 'abc' , number : '45672778282'};

How do I automate this process, so using string and obj I will replace string {} value to obj (key value).

I have tried PUG but not able to parse.

pug.render(str, obj);

Doesn't work for me.

Answer 1

lets see, you want to make something like templating, just like handlebars http://handlebarsjs.com/ .

I will give you this example to make a simple-handlebars for you case:

function render(template, properties)
{
     var result = template;
     for (i in properties)
     {
         result = result.replace("{"+i+"}",properties[i]);
     }
     return result;
}

but this one will only change first occurence of respective properties, if you want you may use this for replace all in the whole template:

function render(template, properties)
{
     var result = template;
     for (i in properties)
     {
         var reg = new RegExp("{"+i+"}","g");
         result = result.replace(reg,properties[i]);
     }
     return result;
}

Answer 2

Here is a variation on the theme.

var str = 'My name is {name} and {name} my age is {age}.';
var obj = {name : 'xyz' , age: 24};

var render = function (str, obj) {
    return Object.keys(obj).reduce((p,c) => {
        return p.split("{" + c + "}").join(obj[c])
    }, str)
}

render(str, obj)

Answer 3

I think you should not re-invent the wheel because the easiest solution is to use some popular node modules.

I suggest 'sprintf-js'.

See my sample code here,

const sprintfJs = require('sprintf-js')

const template = 'hello %(name)s today is %(day)s'
const data = {
  name: 'xxxx',
  day: 'Tuesday'
}

const formattedString = sprintfJs.sprintf(template, data)
console.log(formattedString)

Answer 4

This is possible with single replace call.

var obj = {name : 'xyz' , age: 24};
let c_obj = {};
let wordArr = [];

const res = str.matchAll("{.*?}");

for(const match of res){

    c_obj[match[0]] =  obj[match[0].slice(1,-1)];
    wordArr.push(match[0]);

}

let new_str = str.replace(new RegExp(wordArr.join('|'),'g'), match => c_obj[match]);