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Last Update: 2/6/2019

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Reference > Language > Functions > Characters > Isalphanumeric

isAlphaNumeric()

[Characters]

Description

Analyse if a char is alphanumeric (that is a letter or a numbers). Returns true if thisChar contains either a number or a letter.

Syntax

isAlphaNumeric(thisChar)

Parameters

thisChar: variable. Allowed data types: char

Returns

true: if thisChar is alphanumeric.

Example Code

if (isAlphaNumeric(myChar)) { // tests if myChar isa letter or a number
  Serial.println("The character is alphanumeric");
}
else {
  Serial.println("The character is not alphanumeric");
}