code-boxx/0-JS-PAD-ZERO.MD

## 0-JS-PAD-ZERO.MD

      
    Raw
  

              0-JS-PAD-ZERO.MD
            
          
    JAVASCRIPT ADD LEADING & TRAILING ZEROES

https://code-boxx.com/add-leading-trailing-zeroes-javascript/
LICENSE

Copyright by Code Boxx
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

  
## 1-easy.html
<!DOCTYPE html>
<html>
  <head>
    <title>Easy Zeroes</title>
    <script>
    // (A) THE NUMBERS
    var numA = 123;
    var numB = 123.45;

    // (B) STRING CONCAT
    console.log("000" + numA);
    console.log(numB + "000");

    // (C) PAD STRING
    console.log(numA.toString().padStart(5, 0));
    console.log(numB.toString().padEnd(8, 0));
    </script>
  </head>
  <body></body>
</html>

## 2-pad-zero.html
<!DOCTYPE html>
<html>
  <head>
    <title>Add Leading & Trailing Zeroes</title>
    <script>
    // (A) PAD WITH ZEROES
    //   NUM : THE ORIGINAL NUMBER
    //   LEAD : TOTAL NUMBER OF DIGITALS ALLOWED (WHOLE NUMBERS)
    //   TRAIL : TOTAL NUMBER OF DIGITALS ALLOWED (DECIMAL NUMBERS)
    function padZero (num, lead, trail) {
      // (A1) CONVERT NUMBER TO STRING
      var cString = num.toString();

      // (A2) GET NUMBER OF DIGITS
      var cWhole, cDec, cCheck = cString.indexOf(".");

      // NO DECIMAL PLACES, A WHOLE NUMBER
      if (cCheck == -1) {
        cWhole = cString.length;
        cDec = 0;
        cString += ".";
      }
      // IS A DECIMAL NUMBER
      else {
        cWhole = cCheck;
        cDec = cString.substr(cCheck+1).length;
      }

      // (A3) PAD WITH LEADING ZEROES
      if (cWhole < lead) {
        for (let i=cWhole; i<lead; i++) { cString = "0" + cString; }
      }

      // (A4) PAD WITH TRAILING ZEROES
      if (cDec < trail) {
        for (let i=cDec; i<trail; i++) { cString += "0"; }
      }

      return cString;
    }

    // (B) TEST
    // (B1) WHOLE NUMBER
    var first = padZero(123, 5, 3);
    console.log(first); // 00123.000

    // (B2) DECIMAL
    var second = padZero(123.45, 5, 3);
    console.log(second); // 00123.450
    </script>
  </head>
  <body></body>
</html>

## 3-remove-zero.html
<!DOCTYPE html>
<html>
  <head>
    <title>Remove Zero</title>
    <script>
    // (A) PARSE FLOAT & INT
    console.log(parseFloat("0123.4500")); // 123.45
    console.log(parseInt("0123.4500")); //123

    // (B) USING REGULAR EXPRESSION
    // Credits: https://stackoverflow.com/questions/594325/input-field-value-remove-leading-zeros
    function removeZero (num) {
      return num.replace(/^0+(?!\.|$)/, "");
    }
    console.log(removeZero("000.00")); // 0.0
    console.log(removeZero("00000")); // 0
    console.log(removeZero("012.30")); // 12.30
    </script>
  </head>
  <body></body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>Easy Zeroes</title>
	<script>
	// (A) THE NUMBERS
	var numA = 123;
	var numB = 123.45;

	// (B) STRING CONCAT
	console.log("000" + numA);
	console.log(numB + "000");

	// (C) PAD STRING
	console.log(numA.toString().padStart(5, 0));
	console.log(numB.toString().padEnd(8, 0));
	</script>
	</head>
	<body></body>
	</html>