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Taken from AngelScript

Strings hold an array of bytes or 16bit words depending on the application settings. Normally they are used to store text but can really store any kind of binary data.

There are two types of string constants supported in the AngelScript language, the normal quoted string, and the documentation strings, called heredoc strings.

The normal strings are written between double quotation marks (") or single quotation marks ('). Inside the constant strings some escape sequences can be used to write exact byte values that might not be possible to write in your normal editor.

sequence	value	description
\0	0	null character
\	92	back-slash
\'	39	single quotation mark (apostrophe)
"	34	double quotation mark
\n	10	new line feed
\r	13	carriage return
\t	9	tab character
\xFFFF	0xFFFF	FFFF should be exchanged for a 1 to 4 digit hexadecimal number representing the value wanted. If the application uses 8bit strings then only values up to 255 is accepted.
\uFFFF	0xFFFF	FFFF should be exchanged for the hexadecimal number representing the unicode code point
\UFFFFFFFF	0xFFFFFFFF	FFFFFFFF should be exchanged for the hexadecimal number representing the unicode code point

string str1 = "This is a string with \"escape sequences".";
string str2 = 'If single quotes are used then double quotes can be included without "escape sequences".';

The heredoc strings are designed for inclusion of large portions of text without processing of escape sequences. A heredoc string is surrounded by triple double-quotation marks ("""), and can span multiple lines of code. If the characters following the start of the string until the first linebreak only contains white space, it is automatically removed by the compiler. Likewise if the characters following the last line break until the end of the string only contains white space this is also removed.

string str = """
  This is some text without "escape sequences". This is some text.
  This is some text. This is some text. This is some text. This is
  some text. This is some text. This is some text. This is some
  text. This is some text. This is some text. This is some text.
  This is some text.
  """;

If more than one string constants are written in sequence with only whitespace or comments between them the compiler will concatenate them into one constant.

string str = "First line.\n"
             "Second line.\n"
             "Third line.\n";

The escape sequences and will add the specified unicode code point as a UTF-8 or UTF-16 encoded sequence depending on the application settings. Only valid unicode 5.1 code points are accepted, i.e. code points between U+D800 and U+DFFF (reserved for surrogate pairs) or above U+10FFFF are not accepted.

Supporting string object and functions

Operators

// The assignment operator copies the content of the right hand
// string into the left hand string.
// Assignment of primitive types is allowed, which will do a
// default transformation of the primitive to a string.
= assignment

// The concatenation operator appends the content of the right
// hand string to the end of the left hand string.
// Concatenation of primitives types is allowed, which will do
// a default transformation of the primitive to a string.
+, += concatenation

// Compares the content of the two strings.
==, != equality

// Compares the content of the two strings. The comparison is
// done on the byte values in the strings, which may not
// correspond to alphabetical comparisons for some languages.
<, >, <=, >= comparison

// The index operator gives access to a single byte in the string.
[] index operator

Methods

// Returns the length of the string.
uint length() const;

// Sets the length of the string.
void resize(uint);

// Returns true if the string is empty, i.e. the length is zero.
bool isEmpty() const;

// Returns a string with the content starting at start and the
// number of bytes given by count. The default arguments will
// return the whole string as the new string.
string substr(uint start = 0, int count = -1) const;

// Inserts another string other at position pos in the original string.
void insert(uint pos, const string &in other);

// Erases a range of characters from the string, starting at position
// pos and counting count characters.
void erase(uint pos, int count = -1);

// Find the first occurrence of the value str in the string,
// starting at start. If no occurrence is found a negative value
// will be returned.
int findFirst(const string &in str, uint start = 0) const;

// Find the last occurrence of the value str in the string.
// If start is informed the search will begin at that position, i.e.
// any potential occurrence after that position will not be searched.
// If no occurrence is found a negative value will be returned.
int findLast(const string &in str, int start = -1) const;

// The first variant finds the first character in the string that matches
// on of the characters in chars, starting at start. If no occurrence is
// found a negative value will be returned.
// The second variant finds the first character that doesn't match any of
// those in chars. The third and last variant are the same except they
// start the search from the end of the string.
// These functions work on the individual bytes in the strings. They
// do not attempt to understand encoded characters, e.g. UTF-8 encoded
// characters that can take up to 4 bytes.
int findFirstOf(const string &in chars, int start = 0) const;
int findFirstNotOf(const string &in chars, int start = 0) const;
int findLastOf(const string &in chars, int start = -1) const;
int findLastNotOf(const string &in chars, int start = -1) const;

// Splits the string in smaller strings where the delimiter is found.
array<string> split(const string &in delimiter) const;

Functions

// Concatenates the strings in the array into a large string,
// separated by the delimiter.
string join(const array<string> &in arr, const string &in delimiter)

// Parses the string for an integer value. The base can be 10 or 16
// to support decimal numbers or hexadecimal numbers. If byteCount
// is provided it will be set to the number of bytes that were
// considered as part of the integer value.
int parseInt(const string &in str, uint base = 10, uint &out byteCount = 0)
uint parseUInt(const string &in str, uint base = 10, uint &out byteCount = 0)

// Parses the string for a floating point value. If byteCount is
// provided it will be set to the number of bytes that were considered
// as part of the value.
double parseFloat(const string &in, uint &out byteCount = 0)

// The format functions takes a string that defines how the number should
// be formatted. The string is a combination of the following characters:
//     l = left justify
//     0 = pad with zeroes
//     + = always include the sign, even if positive
//     space = add a space in case of positive number
//     h = hexadecimal integer small letters (not valid for formatFloat)
//     H = hexadecimal integer capital letters (not valid for formatFloat)
//     e = exponent character with small e (only valid for formatFloat)
//     E = exponent character with capital E (only valid for formatFloat)
string formatInt(int val, const string &in options = '', uint width = 0)
string formatUInt(uint val, const string &in options = '', uint width = 0)
string formatFloat(double val, const string &in options = '', uint width = 0, uint precision = 0)

Examples

// Left justify number in string with 10 characters
string justified = formatInt(number, 'l', 10);

// Create hexadecimal representation with
// capital letters, right justified
string hex = formatInt(number, 'H', 10);

// Right justified, padded with zeroes and two digits
// after decimal separator
string num = formatFloat(number, '0', 8, 2);