struts2中用xml配置文件去验证填写信息

xml名字是这样的 actionName-validation.xml 每个action 对应一个xml文件

xml文件和action放在同一个包下

后台验证用户输入是否符合格式要求，不符合，提交后返回对应提示。

//xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE validators PUBLIC
"-//OpenSymphony Group//XWork Validator 1.0.2//EN"
"http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
<validators>
<validator type="requiredstring">
<param name="fieldName">username</param>
<param name="trim">true</param>
<message>必须输入用户名</message>
</validator>

<validator type="regex">
<param name="fieldName">username</param>
<param name="expression"><![CDATA[(w{6,20})]]></param>
<message>用户名长度必须为6至20之间</message>
</validator>

<validator type="requiredstring">
<param name="fieldName">password</param>
<param name="trim">true</param>
<message>必须输入密码</message>
</validator>

<validator type="regex">
<param name="fieldName">password</param>
<param name="expression"><![CDATA[(w{6,20})]]></param>
<message>密码长度必须为6至20之间</message>
</validator>

<validator type="requiredstring">
<param name="fieldName">repassword</param>
<param name="trim">true</param>
<message>必须输入确认密码</message>
</validator>

<validator type="regex">
<param name="fieldName">repassword</param>
<param name="expression"><![CDATA[(w{6,20})]]></param>
<message>确认密码长度必须为6至20之间</message>
</validator>

<validator type="fieldexpression">
<param name="fieldName">repassword</param>
<param name="expression"><![CDATA[(repassword==password)]]></param>
<message>密码和确认密码必须一致</message>
</validator>

<validator type="requiredstring">
<param name="fieldName">nickname</param>
<param name="trim">true</param>
<message>必须输入昵称</message>
</validator>

<validator type="regex">
<param name="fieldName">nickname</param>
<param name="expression"><![CDATA[([u4e00-u9fa5]{2,20})]]></param>
<message>昵称长度必须为2至20之间</message>
</validator>

<validator type="requiredstring">
<param name="fieldName">answer</param>
<param name="trim">true</param>
<message>必须输入密码保护答案</message>
</validator>

<validator type="regex">
<param name="fieldName">answer</param>
<param name="expression"><![CDATA[([u4e00-u9fa5]{5,50})]]></param>
<message>密码保护答案长度必须为5至50之间</message>
</validator>
</validators>

 //HTML文件

<table width="1000" cellpadding="0" cellspacing="0" border="0">
<tr height="100">
<td colspan="2">&nbsp;</td>
</tr>
<tr>
<td align="right" width="300" valign="top"><img src="image/register.gif"></td>
<td width="20">&nbsp;</td>
<td valign="top">
<table width="600" border="1" cellpadding="0" cellspacing="0" style="background-color:#FFFFFF;BORDER-RIGHT:#cccccc 1px solid; BORDER-TOP:#cccccc 1px solid; BORDER-LEFT:#cccccc 1px solid; BORDER-BOTTOM:#cccccc 1px solid; BORDER-COLLAPSE:collapse">
<tr height="30">
<td colspan="3" align="center" background="image/main/l-bg1.jpg"><font color="#ffff66"><b>新博客注册</b></font></td>
</tr>
<tr height="30">
<td align="right" width="160">帐号&nbsp;</td>
<td><input type="text" name="username"/>*</td>

<!--username 就是xml文件中对应的  <param name="fieldName">username</param> 名字-->
<td><s:fielderror><s:param>username</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td align="right">密码&nbsp;</td>
<td><input type="password" name="password"/>*</td>
<td><s:fielderror><s:param>password</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td align="right">确认密码&nbsp;</td>
<td><input type="password" name="repassword"/>*</td>
<td><s:fielderror><s:param>repassword</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td align="right">昵称&nbsp;</td>
<td><input type="text" name="nickname"/>*</td>
<td><s:fielderror><s:param>nickname</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td align="right">密码保护问题&nbsp;</td>
<td>
<select name="question">
<option value="你的生日">你的生日</option>
<option value="你的家乡">你的家乡</option>
<option value="你最喜欢的食物">你最喜欢的食物</option>
</select>*
</td>
<td><s:fielderror><s:param>question</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td align="right">密码保护的答案&nbsp;</td>
<td><input type="text" name="answer"/>*</td>
<td><s:fielderror><s:param>answer</s:param></s:fielderror></td>
</tr>
<tr height="30">
<td colspan="3" align="center"><input type="submit" value="提交"/>
<input type="reset" value="重置"/>
</td>
</tr>
</table>
</td>
</tr>
</table>

//action代码

public class Register extends ActionSupport{

private String username;
private String password;
private String repassword;
private String nickname;
private String question;
private String answer;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getRepassword() {
return repassword;
}
public void setRepassword(String repassword) {
this.repassword = repassword;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
public String getQuestion() {
return question;
}
public void setQuestion(String question) {
this.question = question;
}
public String getAnswer() {
return answer;
}
public void setAnswer(String answer) {
this.answer = answer;
}

public String execute() throws Exception {
System.out.println(this.username);
System.out.println(this.password);
System.out.println(this.repassword);
System.out.println(this.nickname);
System.out.println(this.question);
System.out.println(this.answer);
return SUCCESS;
}
}