javascript - type="number" but still requires a text to number conversion -


i've element (x) of type=number. in work verify it's value number before performing mathematical operations i've concluded elements of type "number", while having builtin validation , helpful input controls, still assign values text , require conversion number before performing mathematical operations. question - true or there wrong in code? here's work. entered number 6. 

        x = document.createelement("input");         x.type = "number";         x.step = "0.1";         x.min = "0";         x.max = "9999";         x.defaultvalue = "1";  var p = document.getelementbyid(x.id).value; isthisnumber(p);   function isthisnumber(z) {     alert(typeof z + " --- " + typeof (z));  // returns "string --- string"      if (z.isnan) {         alert("it's not number");     } else {         alert("it's number");  // returns false - it's number     }      if (z.tofixed) {         alert("it's number");     } else {         alert("it's not number");  // returns false - it's not number     }      var = z + z;     alert("sum : " + a);  // returns "66"      var b = number(z);     var b2 = b + b;     alert("sum : " + b2);  // returns "12" }

ref: https://developer.mozilla.org/en-us/docs/web/html/element/input/number


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