What is the regex for json key?

The regex pattern for json key is `"([^"\\]*(?:\\.[^"\\]*)*)"\s*:`. This pattern validates json object key (quoted string followed by colon).

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /"([^"\\]*(?:\\.[^"\\]*)*)"\s*:/;` and test with `regex.test(yourValue)`. It returns `true` if the value matches.

How do I use this regex in Python?

In Python, use `import re; re.match(r'"([^"\\]*(?:\\.[^"\\]*)*)"\s*:', value)`. The raw string prefix (`r`) prevents Python from interpreting backslashes as escape characters.

Is this regex case-sensitive?

By default, yes. To make it case-insensitive, add the `i` flag in JavaScript (`/"([^"\\]*(?:\\.[^"\\]*)*)"\s*:/i`) or use `re.IGNORECASE` in Python.

Regex for JSON Key

Regex Pattern

"([^"\\]*(?:\\.[^"\\]*)*)"\s*:

JSON object key (quoted string followed by colon)

Quick Answer

The regex pattern for json key is `"([^"\\]*(?:\\.[^"\\]*)*)"\s*:`. JSON object key (quoted string followed by colon). This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
"name": "value"	✓ Matches
"key": 123	✓ Matches
"nested-key": {}	✓ Matches
key: value	✗ No match
'key': value	✗ No match
unquoted: true	✗ No match

Code Examples

javascript

const regex = /"([^"\\]*(?:\\.[^"\\]*)*)"\s*:/;
const isValid = regex.test(value);

python

import re
pattern = r'"([^"\\]*(?:\\.[^"\\]*)*)"\s*:'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /"([^"\\]*(?:\\.[^"\\]*)*)"\s*:/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/"([^"\\]*(?:\\.[^"\\]*)*)"\s*:/', $value)) {
    echo "valid";
}

java

String pattern = ""([^"\\\\]*(?:\\\\.[^"\\\\]*)*)"\\s*:";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

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