String()
Description
Constructs an instance of the String class. There are multiple versions that construct Strings from different data types (i.e. format them as sequences of characters), including:
- a constant string of characters, in double quotes (i.e. a char array)
- a single constant character, in single quotes
- another instance of the String object
- a constant integer or long integer
- a constant integer or long integer, using a specified base
- an integer or long integer variable
- an integer or long integer variable, using a specified base
Constructing a String from a number results in a string that contains the ASCII representation of that number. The default is base ten, so
String thisString = String(13)
gives you the String “13”. You can use other bases, however. For example,
String thisString = String(13, HEX)
gives you the String “D”, which is the hexadecimal representation of the decimal value 13. Or if you prefer binary,
String thisString = String(13, BIN)
gives you the String “1101”, which is the binary representation of 13.
Syntax
String(val)
String(val, base)
Parameters
val
: a variable to format as a String – string, char, byte, int, long, unsigned int, unsigned long
base
(optional) – the base in which to format an integral value
Returns
an instance of the String class
Examples
All of the following are valid declarations for Strings.
String stringOne = "Hello String"; // using a constant String String stringOne = String('a'); // converting a constant char into a String String stringTwo = String("This is a string"); // converting a constant string into a String object String stringOne = String(stringTwo + " with more"); // concatenating two strings String stringOne = String(13); // using a constant integer String stringOne = String(analogRead(0), DEC); // using an int and a base String stringOne = String(45, HEX); // using an int and a base (hexadecimal) String stringOne = String(255, BIN); // using an int and a base (binary) String stringOne = String(millis(), DEC); // using a long and a base
See also
- String
- String Constructor Tutorial
The text of the 86Duino reference is a modification of the Arduino reference, and is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.