7.2: String Functions
- Page ID
- 10701
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String functions are used in computer programming languages to manipulate a string or query information about a string.[1]
Discussion
Most current programming languages include built-in or library functions to process strings. Common examples include case conversion, comparison, concatenation, find, join, length, reverse, split, substring, and trim.
| Function | C++ | C# | Java |
|---|---|---|---|
| case | tolower(), toupper(), etc. | ToLower(), ToUpper(), etc. | toLowerCase(), toUpperCase(), etc. |
| comparison | <, >, ==, etc. | <, >, ==, etc. | <, >, ==, etc. |
| concatenation | +, += | +, += | +, += |
| find | find() | IndexOf() | indexOf() |
| join | N/A | Join() | join() |
| length | length() | Length | length() |
| replace | replace() | Replace() | replace() |
| reverse | reverse() | Reverse() | N/A |
| split | strtok() | Split() | split() |
| substring | substr() | Substring() | substring() |
| trim | N/A | Trim() | trim() |
| Function | JavaScript | Python | Swift |
|---|---|---|---|
| case | toLowerCase(), toUpperCase(), etc. | lower(), upper(), etc. | lowercased(), uppercased() |
| comparison | <, >, ==, etc. | <, >, ==, etc. | <, >, ==, etc. |
| concatenation | +, += | +, += | +, += |
| find | indexOf() | find() | firstIndex() |
| join | join() | join() | joined() |
| length | length | len() | count |
| replace | replace() | replace() | replacingOccurrences() |
| reverse | N/A | string[::-1] | reversed() |
| split | split() | split() | split() |
| substring | substring() | string[start:end] | string[start...end] |
| trim | trim() | strip() | trimmingCharacters() |