<meta charset="utf-8" & gt;
Window. The onl oad=function () {
Var TAB=document. GetElementById (" TAB ");
Var BTN=document. GetElementById (" BTN ");
TAB. SetAttribute (" style ", "width: 0 px;" )
BTN. Onclick=function () {
Var a=TAB. Style. The width;
Var b=parseInt (a);
Var b2=b + 10;
Var a2=b2 + "px";
TAB. Style. The width=a2;
}
}
</script>
<body>