<form name="animatiegifjes"> <input type="text" name="original" size="20" value=1024> <select size="1" name="units"> <option value="Bytes">Bytes</option> <option value="Kb">Kb</option> <option value="Mb">Mb</option> <option value="Gb">Gb</option> </select> <input type="button" value="Bereken" name="B1" onClick="calculate()"></p> </form> <script> var bytevalue=0 function calculate(){ var invalue=document.animatiegifjes.original.value var selectunit=document.animatiegifjes.units.options[document.animatiegifjes.units.selectedIndex].value if (selectunit=="Bytes") bytevalue=invalue else if (selectunit=="Kb") bytevalue=invalue*1024 else if (selectunit=="Mb") bytevalue=invalue*1024*1024 else if (selectunit=="Gb") bytevalue=invalue*1024*1024*1024 alert (invalue+" "+selectunit+" is gelijk aan:\n\n- "+bytevalue+" Bytes\n- "+Math.round(bytevalue/1024)+" Kb\n- "+Math.round(bytevalue/1024/1024)+" Mb\n- "+Math.round(bytevalue/1024/1024/1024)+" Gb\n") } </script>