What are the ways to convert strings to integers in JavaScript and which one is the fastest?

Question

What are the methods? Which method is fastest!
Number()
parseInt()

Answer 1

(unofficial) test results, see for yourself

Number()

parseInt()

Math.floor()

Math.round()

Math.ceil()

|0

^0

-0

Math.floor+

-Math.floor-

--split[0]

+split[0]

Answer 2

+'123'

Answer 3

Math.floor(+'123.123');

-Math.floor(-'123.123')

-(-'123.213'.split('.')[0]);

+'123.213'.split('.')[0]

There are many conversion methods, but they are all small tricks of using operators for implicit conversion.

In addition to priority and associativity, please also note that different operands will affect the implicit conversion of operators.

Answer 4

There are also these methods,
'3.1425' | 0
'7.86'^0
'123'-0

I feel like the methods specifically used for conversion are faster, like parseInt and Number you mentioned. I haven’t tried it personally

Answer 5

var a = 1.123445;
a >> 0;

Answer 6

String inString = ""; // The inString variable is used to store the value from the input

Void setup () {
  // Open serial port with baudrate 9600
  Serial.begin (9600);
  While (! Serial) {
    ; // wait Serial port is turned on (just with Arduino Leonardo circuit)
  }

  // Send a message that the setup function has finished
  Serial.println (" n nChanges compared to:");
  Serial.println ();
}

Void loop () {
  // Read the value from Serial
  While (Serial.available ()> 0) {
    Int inChar = Serial.read ();
    If (isDigit (inChar)) {// Check function NUMBER is a digital character
      // and add strings. Otherwise you will add an integer to it: P
      InString + = (char) inChar;
    }
    // If inChar is a newline character. I print the results
    If (inChar == ' n') {// One character uses '(single quote) and one string to use' (double quotes)
      Serial.print ("value:");
      Serial.println (inString.toInt ());
      Serial.print ("string:");
      Serial.println (inString);
      // delete the value of the inString variable
      InString = "";
    }
  }
}
photo editor

Answer 7

Also~~'123.45'

Answer 8

var a = '1'

var b = a * 1

b is number