ヘッダ部分
<SCRIPT LANGUAGE="JavaScript">
function strEsc(form) {
form.postesc.value = escape(form.preesc.value)
}
function strUnesc(form) {
form.postunesc.value = unescape(form.preunesc.value)
}
</SCRIPT>
ボディ部分
<FORM>
<INPUT TYPE="text" NAME="preesc" SIZE="40" VALUE="こんにちは">
<INPUT TYPE="button" NAME="escexe" VALUE=" escape " onClick="strEsc(this.form)">
<INPUT TYPE="text" NAME="postesc" SIZE="40"><P>
<INPUT TYPE="text" NAME="preunesc" SIZE="40" VALUE="%82%B1%82%F1%82%CE%82%F1%82%ED">
<INPUT TYPE="button" NAME="unescexe" VALUE=" unescape"onClick="strUnesc(this.form)">
<INPUT TYPE="text" NAME="postunesc" SIZE="40">
</FORM>