JSFiddle - React, Tailwind, and code Playground

HTML

<param name="movie" value="/Flash/Dg_Inverse.swf?secEncCode=9e2ec595c926065318629a6dfea6b2ed">

JavaScript

var value = $("param[name='movie']").val();//get attribyte value
if(value && (value = value.match(/secEncCode=(\w+)/))){//reg exp
  value = value[1];//get first pocket
  alert(value);//res
}