(:source lang=arduino tabwidth=4:)

(:sourceend:)

    Serial.write(myStr[i]);
    Serial.println();

  delay(5000); // slow down the program

Note also that a properly formatted string ends with the NULL symbol, which has ASCII value 0.

sizeof(variable)

for (i = 0; i < (sizeof(myInts)/sizeof(int)) - 1; i++) {
  // do something with myInts[i]
}

The sizeof operator is useful for dealing with arrays (such as strings) where it is convenient to be able to change the size of the array without breaking other parts of the program.

This program prints out a text string one character at a time. Try changing the text phrase.

The sizeof operator returns the number of bytes in a variable type, or the number of bytes occupied by an array.

sizeof (variable)

sizeof variable

Both forms are accepted by the compiler

Parameters

variable: any variable type or array (e.g. int, float, byte)

Example code

This program prints out the text string a character at a time. Try changing the text phrase.

char myStr[] = "this is a test";

void setup(){

  Serial.begin(9600);

}

void loop() {

  for (i = 0; i < sizeof(myStr) - 1; i++){
    Serial.print(i, DEC);
    Serial.print(" = ");
    Serial.println(myStr[i], BYTE);
  }

}

Note that sizeof returns the total number of bytes. So for larger variable types such as ints, the for loop would look something like this.

[@ for (i = 0; i < (sizeof(myStr)/sizeof(int)) - 1; i++) @)

sizeof

Description

The sizeof operator returns the number of bytes in a variable type, or the number of bytes occupied by an array, to find the

Syntax

(type)(variable)

Parameters:

type: any variable type (e.g. int, float, byte)

variable: any variable or constant

Example

int i;
float f;

f = 3.6; 
i = (int) f; // now i is 3

Note

When casting from a float to an int, the value is truncated not rounded. So both (int) 3.2 and (int) 3.7 are 3.

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