How to Use isControl() in Arduino?

The isControl() function is used to determine if a character is a control character. A control character or a non-printing character (NPC) is a code point (a number) in a character set that does not represent a written symbol. All entries in the ASCII table below code 32 are of this kind. This includes characters like '
', '\t', and so on.

Syntax

The syntax of the isControl function is as follows −

isControl(myChar)

Where myChar is the character being evaluated. If it is a control character, this function returns True, otherwise False.

Example

The following example illustrates how to use this function −

void setup() {
   Serial.begin(9600);
   Serial.println();
   char c1 = 'a';
   char c2 = '<br>';
   if (isControl(c1)) {
      Serial.println("c1 is a control char");
   } else {
      Serial.println("c1 is NOT a control char");
   }
   if (isControl(c2)) {
      Serial.println("c2 is a control char");
   } else {
      Serial.println("c2 is NOT a control char");
   }
}
void loop() {
}

Output

The Serial Monitor output is shown below −