Comment en Valider JSON

问题

You avoir un JSON chaîne de un untrusted ou hand-edited source et besoin en vérifier it est syntactically correct.

Prérequis

• Understanding of JSON syntax
• Ability to read error messages

Étapes

1. 1. Parse the JSON string

   Attempt to parse the string as JSON. A standards-compliant parser will throw an error if the syntax is invalid. Common errors include trailing commas, single-quoted strings, and missing brackets.

   entrée

   {"name":"John",}

   输出

   Error: Unexpected token } at position 15

2. 2. Interpret the error location

   If parsing fails, the error message typically includes the position or line number of the problem. Go to that location in the input and fix the syntax issue. Repeat until parsing succeeds.

   entrée

   position 15

   输出

   trailing comma before }

3. 3. Optionally validate against a schema

   If you have a JSON Schema, validate the parsed JSON against it to check not just syntax but structure (required fields, types, value ranges). Schema validation catches semantic errors that syntax parsing cannot.

   entrée

   JSON + schema

   输出

   valid or schema errors

Résultat attendu

Confirmation ce le JSON est valide, ou un effacer erreur message identifying le problem et its location.

Erreurs courantes

Trailing comma in object or array

JSON does not allow trailing commas. Remove the comma after the last element.

Single-quoted strings

JSON requires double quotes for strings and keys. Replace single quotes with double quotes.

Dépannage指引

• If the error position seems wrong, check for invisible characters like BOM or zero-width spaces.
• Use a JSON validator with line and column numbers for easier debugging.

Limites de sécurité

• Parsing untrusted JSON is generally safe, but do not use eval() to parse JSON — it can execute arbitrary code. Use JSON.parse instead.