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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:

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 ) ;

[Get Code]

gives you the String "13". You can use other bases, however. For example, >

[Get Code]

gives you the String "13". You can use other bases, however. For example, >

String thisString = String( 13 , HEX ) ;
[Get Code]

gives you the String "13". You can use other bases, however. For example, > [Get Code]

gives you the String "D", which is the hexadecimal representation of decimal value 13. Or if you prefer binary, >

[Get Code]

gives you the String "D", which is the hexadecimal representation of decimal value 13. Or if you prefer binary, >

String thisString = String( 13 , BIN ) ;
[Get Code]

gives you the String "D", which is the hexadecimal representation of decimal value 13. Or if you prefer binary, > [Get Code]

gives you the String "1101", which is the binary representation of 13.>

Syntax

String(val)
String(val, base)
String(val, decimalPlaces)

Parameters

val: a variable to format as a String - string, char, byte, int, long, unsigned int, unsigned long, float, double
base (optional) - the base in which to format an integral value
decimalPlaces (only if val is float or double) - the desired decimal places

Returns

an instance of the String class

Examples

All of the following are valid declarations for Strings.

[Get Code]

gives you the String "1101", which is the binary representation of 13.>

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
String stringOne =  String( 5.698 , 3 ) ;                                // using a float and the decimal places
[Get Code]

gives you the String "1101", which is the binary representation of 13.> [Get Code]

See also


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