struts validator 的简单介绍(一)

花费时间找,但找到的几个地方的资料讲解均不是很系统,因此在这里大略介绍struts validator的使用.我所使用的是struts 1.3.8
首先要配置好struts-config.xml,如下:

xml 代码

xml version="1.0" encoding="ISO-8859-1" ?>


          "-//Apache Software Foundation//DTD Struts Configuration 1.3//EN"
          "http://struts.apache.org/dtds/struts-config_1_3.dtd">

<struts-config>

<!---->

    <form-beans>
    <form-bean name="validationForm"  type="com.ibm.struts.validation.ValidationForm"/>
    <form-beans>

<!---->

    <global-forwards>
        <!---->
        <!---->
        <forward
            name="welcome"
            path="/Welcome.do"/>
    <!---->global-forwards>


<!---->

    <action-mappings>
            <!---->
            <!---->
        <action
            path="/Welcome"
            forward="/pages/Welcome.jsp"/>
        <action path="/TestSimpleValidation"
                forward="/pages/test_validation.jsp" />
        <action path="/SubmitValid"
                type="com.ibm.struts.validation.ValidationAction"
                name="validationForm"
                scope="request"
                validate="true"
                input="/pages/test_validation.jsp">
          <forward name="success" path="/pages/success.jsp" redirect="true"/>
          <forward name="failure" path="/pages/test_validation.jsp"
                   redirect="true" />
        <!---->action>
    <!---->action-mappings>


<!---->

    <message-resources parameter="MessageResources" >
  <!---->message-resources>
  <message-resources key="zh_CN" parameter="MessageResources_zh_CN" />


<!---->
  <!---->

  <plug-in className="org.apache.struts.validator.ValidatorPlugIn">
    <set-property
        property="pathnames"
        value="/org/apache/struts/validator/validator-rules.xml,
               /WEB-INF/validation.xml"/>
  <!---->plug-in>

<!---->struts-config>

上面59行至64行,增加validator的功能.第12行,设置form,第36行至45行,设置action,由于validator主要的使用不涉及form,action,因此这里不做详细介绍,要提的是form需要继承org.apache.struts.validator.ValidatorForm,

/WEB-INF/validation.xml文件介绍,这个文件主是要针对每个字段设置验证规则,

xml 代码

xml version="1.0" encoding="ISO-8859-1" ?>

     "-//Apache Software Foundation//DTD Commons Validator Rules Configuration 1.3.0//EN"
     "http://jakarta.apache.org/commons/dtds/validator_1_3_0.dtd">

<form-validation>

    <formset>
        <!---->
        <form name="validationForm">
            <field property="username" depends="required">
                <arg key="prompt.username"/>
            <!---->field>
            <field
                property="password"
                depends="required,mask">
                    <arg key="prompt.password"/>
                    <var>
                        <var-name>mask<!---->var-name>
                        <var-value>^t[0-9]n$<!---->var-value>
                    <!---->var>
            <!---->field>
        <!---->form>

    <!---->formset>

<!---->form-validation>

容易理解的不做介绍,第11行depends=required的意思当然是该字段是必需的,不能为空,所在资源文件里的相应的错误信息是这样的"errors.required={0} is required.",接下来的第12行,就是定义{0}参数是用什么替代,用的是也是资源文件里的"prompt.username=\u5e10\u53f7"

资源文件

xml 代码

# -- standard errors --
errors.header=validation error message
errors.prefix=<LI>
errors.suffix=<!---->LI>
errors.footer=<!---->UL>
# -- validator --
errors.invalid={0} is invalid.
errors.maxlength={0} can not be greater than {1} characters.
errors.minlength={0} can not be less than {1} characters.
errors.range={0} is not in the range {1} through {2}.
errors.required={0} is required.
errors.byte={0} must be an byte.
errors.date={0} is not a date.
errors.double={0} must be an double.
errors.float={0} must be an float.
errors.integer={0} must be an integer.
errors.long={0} must be an long.
errors.short={0} must be an short.
errors.creditcard={0} is not a valid credit card number.
errors.email={0} is an invalid e-mail address.
# -- other --
errors.cancel=Operation cancelled.
errors.detail={0}
errors.general=The process did not complete. Details should follow.
errors.token=Request could not be completed. Operation is not in sequence.
# -- welcome --
welcome.title=Struts Blank Application
welcome.heading=Welcome!
welcome.message=To get started on your own application, copy the struts-blank.war to a new WAR file using the name for your application. Place it in your container's "webapp" folder (or equivalent), and let your container auto-deploy the application. Edit the skeleton configuration files as needed, restart your container, and you are on your way! (You can find the MessageResources.properties file with this message in the /WEB-INF/src folder.)
valid.title=\u7b80\u5355\u9a8c\u8bc1
prompt.username=\u5e10\u53f7
prompt.password=\u5bc6\u7801
prompt.phone=\u7535\u8bdd\u53f7\u7801
prompt.email=E-Mail
prompt.url=URL

最后,要在jsp里引用错误提示信息:

xml 代码

<logic:messagesPresent>
   <bean:message key="errors.header"/>
   <ul>
   <html:messages id="error">
      <li><bean:write name="error"/></li>
   </html:messages>
   </ul><hr />
</logic:messagesPresent>

将这一段代码放在body后面即可.

参考资源:
http://struts.apache.org/1.3.8/faqs/validator.html
http://struts.apache.org/1.3.8/userGuide/building_view.html#validator
struts-examples-1.3.8示例里有validator的例子