Comparison of programming languages (string functions)

String functions are special tools used in computer programming languages to work with words and sentences, called strings. These tools help change or find information about strings in many ways.

Most programming languages that can handle words and sentences will have some string functions, even if there are other ways to work with them. In languages where everything is built from objects, string functions are often parts of string objects themselves. In some other languages, strings are shown as lists of tiny pieces, so tools that work with lists can also work with strings.

A very basic example of a string function is the length(string) function. This tells you how many letters are in a word or sentence. For example, length("hello world") would return 11, because "hello world" has 11 letters and spaces.

Many languages have similar string functions, which can help make coding easier and less confusing.

Common string functions (multi language reference)

String functions are common tools in many programming languages. They help manipulate or get information about text. These functions have different names across languages but do similar tasks.

CharAt

The CharAt function gets a single character from a specific position in a string. For example, in Pascal, to get the second character of "Hello, World", you would use MyStr, which returns 'e'.

Compare (integer result)

Some languages compare strings and return an integer. For example, in Perl, "hello" cmp "world" returns -1, showing that "hello" comes before "world" alphabetically.

Compare (relational operator-based, Boolean result)

Other languages use operators to compare strings and return a true or false result. In Erlang, "hello" > "world" returns false because "hello" is not greater than "world".

Concatenate

Concatenation joins two or more strings together. In C#, "abc" + "def" returns "abcdef".

Contains

The Contains function checks if a string includes another string. In C#, "Hello mate".Contains("e") returns true because "e" is in "Hello mate".

Equality

Equality checks if two strings are exactly the same. In C#, "hello" == "world" returns false.

Find

The Find function locates the position of a substring within a string. In Common Lisp, (search "e" "Hello mate") returns 1, showing that "e" starts at position 1 in "Hello mate".

Format

Format functions arrange strings with placeholders for values. In C#, String.Format("My {0} costs {1:C2}", "pen", 19.99) returns "My pen costs $19.99".

Inequality

Inequality checks if two strings are not the same. In C#, "hello" != "world" returns true.

Join

Join combines a list of strings into one string, often with a separator. In C#, String.Join("-", {"a", "b", "c"}) returns "a-b-c".

Length

Length returns the number of characters in a string. In C#, "hello".Length returns 5.

Lowercase

Lowercase changes all characters in a string to lowercase. In C#, "Wiki means fast?".ToLower() returns "wiki means fast?".

Replace

Replace swaps one substring for another in a string. In C#, "effffff".Replace("f", "jump") returns "ejumpjumpjumpjumpjumpjump".

Reverse

Reverse turns a string backwards. In Smalltalk, 'hello' reversed returns 'olleh'.

Right

Right gets a certain number of characters from the end of a string. In Visual Basic, Right("sandroguidi", 3) returns "idi".

Split

Split divides a string into parts based on a separator. In C#, "abc,defgh,ijk".Split(',') returns {"abc", "defgh", "ijk"}.

Substring

Substring takes a part of a string from a starting point. In C#, "abc".Substring(1, 1) returns "b".

Uppercase

Uppercase changes all characters in a string to uppercase. In C#, "Wiki means fast?".ToUpper() returns "WIKI MEANS FAST?".

Trim

Trim removes extra spaces from the start and end of a string. In JavaScript, a custom trim function can be added to remove spaces from both ends of a string.