Programming Fundamentals/String Functions
Overview
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()
|
Key Terms
- case
- A function that either makes a string all uppercase or lowercase depending on which mode is used.
- comparison
- Determines if the value (string or non-string), is less than, greater than, or equal to the value it's being compared to.
- concatenate
- Join character strings end-to-end.[2]
- find
- Checks if a character in a string exists and if it does, finds the location of that character in the string.
- join
- Joins strings together using a character of the person's choosing.
- length
- Finds how many characters are in a string, or the number of elements in an array.
- replace
- Replaces all instances of one character in a string with another.
- reverse
- Places all characters of a string or elements in an array in reverse order.
- split
- Divides a string's content onto separate lines based off a chosen character.
- substring
- Creates a smaller string by using characters from a bigger string.[3]
- trim
- Remove leading and trailing spaces from a string.[4]