JAVASCRIPT ⇢ generate a password with 11 characters

fncGeneratePwd.js

//--------------------------------------------------
// purpose :  generate a password with 11 characters
// return a string
//--------------------------------------------------
  function fncGeneratePwd() {
    
    const sCharSymbols = "+=?!@#$%*"; // you can add more symbols
    const sCharDigits = "0123456789";
    const sCharUpper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    const sCharLower = "abcdefghijklmnopqrstuvwxyz";

    var sRetval = "";
    for (let i = 1; i < 5; i++) {
      switch(i) {
          // in this case, the total amount of chars below is  : 2 + 2 + 2 + 5 = 11
          // you can change this or you can random them, in order to force security.
          // you can also add more than 11 chars
          case 1: sPos=9; sNbr=2; sCodes = sCharSymbols; break; // have 2 symbols
          case 2: sPos=10; sNbr=2; sCodes = sCharDigits; break; // have 2 digits
          case 3: sPos=26; sNbr=2; sCodes = sCharUpper; break; // have 4 upper case chars
          case 4: sPos=26; sNbr=5; sCodes = sCharLower; break; // have 5 lower case chars
      }
		
      for (let k = 0; k < sNbr; k++) {
        sRetval += sCodes.charAt(Math.floor(Math.random(1) * (sPos)));
      }
    }
    
    // this replace all characters positions in the string randomly
    var sRetval = sRetval.split('').sort(function(){return 0.5-Math.random()}).join('');

    return sRetval;

}