Replace single quotes with double quotes
JavaScript object syntax and JSON syntax are different. JSON requires double quotes around keys and string values. Bare property names and single-quoted strings are invalid.
Invalid: {name: 'Alex'}
Valid: {"name": "Alex"}Remove trailing commas and comments
JSON does not permit a comma after the last object property or array element. It also does not permit // or block comments. Delete comments or store explanatory information in a normal string property if your schema allows it.
Invalid: [1, 2, 3,] Valid: [1, 2, 3]
Escape special characters inside strings
A literal double quote needs a backslash. A backslash itself must also be escaped. Actual newlines cannot appear unescaped inside a JSON string; use the two-character escape sequence \n instead.
{"message":"He said \"hello\"","path":"C:\\temp"}Match every opening delimiter
An object begins with { and ends with }. An array begins with [ and ends with ]. Work from the innermost structure outward, and validate after each correction. Do not use eval to bypass JSON parsing errors.