<HTML>
<HEAD>
<SCRIPT LANGUAGE="JavaScript">
function calc()
{
with(document.form01)
txt02.value = eval(txt01.value);
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="form01">
計算式:<INPUT TYPE="TEXT" NAME="txt01" SIZE="30">
<INPUT TYPE="button" VALUE="計算" onClick="calc()"><BR>
計算結果:<INPUT TYPE="TEXT" NAME="txt02" SIZE="10">
</FORM>
</BODY>
</HTML>