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Instead of matching a particular string, you can choose to match any character in a range, like:
/[a-z]/ //a, b, c, ... , x, y, z
/[A-Z]/ //A, B, C, ... , X, Y, Z
/[a-c]/ //a, b, c
/[0-9]/ //0, 1, 2, 3, ... , 8, 9These regexes match strings that contain at least one of the characters in those ranges:
/[a-z]/.test('a') //✅
/[a-z]/.test('1') //❌
/[a-z]/.test('A') //❌
/[a-c]/.test('d') //❌
/[a-c]/.test('dc') //✅Ranges can be combined:
/[A-Za-z0-9]//[A-Za-z0-9]/.test('a') //✅
/[A-Za-z0-9]/.test('1') //✅
/[A-Za-z0-9]/.test('A') //✅Lessons in this unit:
| 0: | Introduction |
| 1: | Introduction |
| 2: | Anchoring |
| 3: | ▶︎ Match Items in Ranges |
| 4: | Matching a Range Item Multiple Times |
| 5: | Negating a Pattern |
| 6: | Meta Characters |
| 7: | Regular Expressions Choices |
| 8: | Quantifiers |
| 9: | Optional Items |
| 10: | Groups |
| 11: | Capturing Groups |
| 12: | Using match and exec Without Groups |
| 13: | Noncapturing Groups |
| 14: | Flags |
| 15: | Inspecting a Regex |
| 16: | Escaping |
| 17: | String Boundaries |
| 18: | Replacing |
| 19: | Greediness |
| 20: | Lookaheads |
| 21: | Lookbehinds |
| 22: | Unicode |
| 23: | Unicode Property Escapes |
| 24: | Examples |