string

Strings have many methods attached to them for manipulating text.

A string is composed of bytes which make up characters. Every character is at least one byte, but a character may also be more than one byte. The traditional ASCII characters are all single bytes. Characters are also refered to as code points or unicode characters.

Class Methods

static varArg string Format(string format, ...): Creates a string using a [format string] and any amount of arguments.

static int CharLower(int ch): Returns the lowercase version of ch.

static int CharUpper(int ch): Returns the uppercase version of ch.

Overview of class methods

CharLower, CharUpper, Format

Instance Methods

Querying

uint Length() const: Returns the number of bytes in this string.

int CodePointCount() const: Returns the number of characters in this string.

int, int GetNextCodePoint(int pos) const: Returns the next character from the byte pos onwards, and the byte position of the next character.

int ByteAt(int pos) const: Returns the byte at pos as an integer.

int IndexOf(string substr, int startIndex = 0) const: Returns the first index of substr starting from the left at start.

int RightIndexOf(string substr, int endIndex = int.Max) const: Returns the first index of substr starting from the right at end.

Copy Modification

string Filter(): Replaces escape sequences in a string with escaped characters as a new string.

string Left(int len) const: Returns the first len bytes as a new string.

string Mid(int pos = 0, int len = int.Max) const: Returns len bytes starting at pos as a new string.

string MakeUpper() const: Converts all characters in the string to uppercase and returns the new string.

string MakeLower() const: Converts all characters in the string to lowercase and returns the new string.

void Split(out array<string> tokens, string delimiter, EmptyTokenType keepEmpty = TOK_KEEPEMPTY) const: Splits the string by each delimiter into tokens. keepEmpty describes whether the function should keep or discard empty strings found while splitting.

In-Place Modification

varArg void AppendFormat(string format, ...): Works like Format, but appends the result to the string.

void Remove(int index, int amount): Removes amount bytes starting at index in-place.

void Replace(string pattern, string replacement): Replaces all instances of pattern with replacement in-place.

void Truncate(int newlen): Truncates the string to len bytes in-place.

void AppendCharacter(int ch): Appends ch to the end of the string in-place.

void DeleteLastCharacter(): Deletes the last character of the string in-place.

Conversions

double ToDouble() const: Interprets the string as a double precision floating point number.

int ToInt(int base = 0) const: Interprets the string as a base base integer, guessing the base if it is 0.

Deprecated

Legacy — Do not use

deprecated("4.1") void ToLower(): Converts all bytes in the string to lowercase in-place. Use MakeLower instead.

deprecated("4.1") void ToUpper(): Converts all bytes in the string to uppercase in-place. Use MakeUpper instead.

deprecated("4.1") string CharAt(int pos) const: Returns the byte at pos as a new string. Use CodePointCount and GetNextCodePoint instead. An example of replacing CharAt is available below.

deprecated("4.1") int CharCodeAt(int pos) const: Returns the byte at pos as an integer. Use either ByteAt or CodePointCount and GetNextCodePoint instead. If you specifically want one byte from the string, use ByteAt. Otherwise, if you want one character, use CodePointCount and GetNextCodePoint. An example of replacing CharCodeAt is available below.

deprecated("3.5.1") int LastIndexOf(string substr, int endIndex = int.Max) const: Broken. Use RightIndexOf instead.

Overview of instance methods

AppendCharacter, AppendFormat, ByteAt, CharAt, CharCodeAt, CodePointCount, DeleteLastCharacter, Filter, GetNextCodePoint, IndexOf, LastIndexOf, Left, Length, MakeLower, MakeUpper, Mid, Remove, Replace, RightIndexOf, Split, ToDouble, ToInt, ToLower, ToUpper, Truncate

Replacing CharAt

// Old code:
if(str.Length() < 3)
	return;

string theThirdCharacter = str.CharAt(2);

// New code:
int leftIndex = -1, rightIndex = -1;

for(int i = 0, j = 0, n = str.CodePointCount(); i < n; j++)
{
	int code;

	[code, i] = str.GetNextCodePoint(i);

	if(j == 2)
		leftIndex = i;
	else if(j == 3)
	{
		rightIndex = i;
		break;
	}
}

if(leftIndex == -1)
	return;

if(rightIndex == -1)
	rightIndex = str.Length() - leftIndex;

string theThirdCharacter = str.Mid(leftIndex, rightIndex - leftIndex);

Replacing CharCodeAt

// Old code:
if(str.Length() < 3)
	return;

int theThirdCharacter = str.CharCodeAt(2);

// New code:
int theThirdCharacter = -1;

for(int i = 0, j = 0, n = str.CodePointCount(); i < n; j++)
{
	int code;

	[code, i] = str.GetNextCodePoint(i);

	if(j == 2)
	{
		theThirdCharacter = code;
		break;
	}
}

if(theThirdCharacter == -1)
	return;