Question 241973 in Javascript Question posted in
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Javascript – Regex for converting object notation to array values

I am trying to convert objects defined within a file into arrays.

I am using JSON.parse on the matched objects.

Some of the multi-line objects are not being replaced.

const txtara = document.querySelector('#demo');

const fixJSON = (invalidJson) => invalidJson
  .replace(/(w+)(?=s*:)/g, '"$1"') // Quote keys
  .replace(/,}/, '}')               // Remove stray commas
  .replace(/,ns*}/, '}');         // Remove stray commas (multiline)

const jsonObjectToArray = (jsonObject) => {
  const obj = JSON.parse(fixJSON(jsonObject));
  return JSON.stringify(Object.values(obj));
}

let content = txtara.value
  // Inline object
    .replace(/({(.+)})/g, (match, json) => jsonObjectToArray(json))
  // Multi-line object
    .replace(/({s*n(?:s*w+s*:s*.+,?n)+s*})/, (match, json) => jsonObjectToArray(json));

txtara.value = content;
*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  height: 100%;
  padding: 0;
  margin: 0;
}

body {
  display: flex;
}

#demo {
  flex: 1;
  resize: none;
  color: #EEE;
  background: #222;
  padding: 0.5rem;
}
<textarea id="demo">
{x:1,y:2}
{x:1,y:2,z:3}
{x:1,y:2,z:3,}
{ x: 1, y: 2, z: 3 }
{
  x: 1,
  y: 2,
}
{
  x: 1,
  y: 2
}
{
  x: 1,
  y: 2,
  z: 3
}
{
  x: 1,
  y: 2,
  z: 3,
}
</textarea>
Tags:

2

Answers


  1. 0

    If you need only numbers, then your answer is

    function textToNumberArrays(text) {
  return text.match(/{[^}]}/g) // match {...}
    .map(obj => {
      return obj.match(/d+(.d+)?/g) // match 123 and 123.456
        .map(n => Number(n)) // convert match strings to numbers
    })
}
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  2. 0

    You can use eval() and a sliding window that you expand whenever eval() throws an error:

    const textarea = document.getElementById('textarea')

const parseButton = document.getElementById('parseButton')

parseButton.addEventListener('click', () => {
  const parts = textarea.value.split('n');
  const parsed = [];
  
  let from = 0;
  let to = 0;
  let n = 1; 
  
  while (from < parts.length && to <= parts.length) {
    try {
      to = from + n;
      
      const parsedPart = eval(`(${ parts.slice(from, to).join('') })`)
      
      parsed.push(parsedPart);
      
      from = to;      
      n = 1;
    } catch (err) {
      ++n;
    }
  }
  
  console.log(`${ parsed.length } objects found = `, parsed);
})
    body {
  display: flex;
  flex-direction: column;
  margin: 8px;
}

#textarea {
  display: block;
  width: 100%;
  height: calc(100vh - 56px);
  resize: none;
  flex: 1 0 auto;
  box-sizing: border-box;
}

#parseButton {
  height: 32px;
  margin-top: 8px;
}
    <textarea id="textarea">
{x:1,y:2}
{x:1,y:2,z:3}
{x:1,y:2,z:3,}
{ x: 1, y: 2, z: 3 }
{
  x: 1,
  y: 2,
}
{
  x: 1,
  y: 2
}
{
  x: 1,
  y: 2,
  z: 3
}
{
  x: 1,
  y: 2,
  z: 3,
}
</textarea>

<button id="parseButton">Parse</button>

    But keep in mind eval should only be used in trusted environments:

    Warning: Executing JavaScript from a string is an enormous security risk. It is far too easy for a bad actor to run arbitrary code when you use eval().

    See Never use eval()!.

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