textCounter--之后要学习

function textCounter(field, countfield, maxlimit){
　　if (field.value.length > maxlimit){
　　if( field.value.indexOf(" ") == maxlimit-1){
　　field.value = field.value.substring(0, maxlimit-1);
　　}else{
　　field.value = field.value.substring(0, maxlimit);
　　}
　　}else{
　　countfield.value = maxlimit - field.value.length;
　　}
　}

<tr>
<td width="100" align="right" valign="top" class="row4">
<bean:message key="reservation.ConfContents" />
:
</td>
<td class="row2" align="center">
<html:textarea property="conf_subject" cols="32" rows="5"
styleClass="input2" style="100%"
onkeydown="textCounter(conf_subject,remLen,255);"
onkeyup="textCounter(conf_subject,remLen,255);"
onmouseup="textCounter(conf_subject,remLen,255);"
onmousedown="textCounter(conf_subject,remLen,255);"
onmouseover="textCounter(conf_subject,remLen,255);"
onmouseout="textCounter(conf_subject,remLen,255);">
</html:textarea>
<br>
<bean:message key="reservation.InputLimit.prefix" />
<html:text property="remLen" readonly="true" size="4" maxlength="3" />
<bean:message key="reservation.InputLimit.suffix" />
</td>
</tr>