List a Range

I want to alert the text to 11,12,13,14,15,3,3,4,5,20,21,22,23,24,25

but the result is 11,12,13,14,15, 11,12,13,14,15, 11,12,13,14,15,3-5, 20-25

here is my Script:

var myText = "11-15, 3, 3-5, 20-25";

var mySplitText = myText.split(", ");

myRangeList ="";

var myHyphenSearch = mySplitText.toString().search(/-/g);;

//alert(myHyphenSearch);

if(mySplitText.content = "-"){

for(var k=0; mySplitText.length>k; k++){

var patt = new RegExp(/ \d*-/i);

var res = patt.exec(myText);

var myFI = Number(mySplitText.toString().indexOf(res));

var myMI=Number(mySplitText.toString().indexOf("-"));

var myLI=Number(mySplitText.toString().indexOf(",", "-"));

var myFirstDigit = mySplitText.toString().substring(myFI, myMI);

var myLastDigit = mySplitText.toString().substring(myMI+1, myLI);

for(var i=myFirstDigit; myLastDigit>=i; i++){

    myRangeList += i+",";

    }//end of for Loop

var myRestText = mySplitText.toString().substring(myLI);

var myNewText = myRangeList+myRestText;

var myNewTextString = myNewText.replace(/,,/g,",");

    }//end of for Loop

alert(myNewTextString);

  }