Arduino Reference - StringConstructor

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String

## 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 "1011", 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 Constructor Tutorial

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