Struts的html标签是个很好用的东东，但有时候不能完全满足要求，我们也许需要定制自己的标签。一点困难在于我们如何为其赋值呢？
用Struts提供的一个工具类， org.apache.struts.util.RequestUtils，它的lookup方法将在pageContext范围内搜索bean的属性值
RequestUtils.lookup(super.pageContext, Constants.BEAN_KEY,p1,null)
下面这个例子演示了如何把2个inputs 做成一个标签。
//Tag: import javax.servlet.jsp.JspException; import org.apache.struts.taglib.html.Constants; public class TwoInputsTag extends BodyTagSupport { //JSP:
package com.tag;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import org.apache.struts.util.RequestUtils;
private String p1;
private String p2;
public String getP1() {
return p1 ;
}
public void setP1(String p1) {
this.p1 = p1;
}
public String getP2() {
return p2;
}
public void setP2(String p2) {
this.p2 = p2;
}
public int doStartTag() throws JspException{
JspWriter out = pageContext.getOut();
try{
Object p1Obj = RequestUtils.lookup(super.pageContext, Constants.BEAN_KEY,p1,null) ;
Object p2Obj = RequestUtils.lookup(super.pageContext, Constants.BEAN_KEY,p2,null) ;
String p1Value = p1Obj == null ? "" :(String)p1Obj ;
String p2Value = p2Obj == null ? "" :(String)p2Obj ;
String outs =
"<input type=\"text\" name=\""+p1+"\" size=\"16\" value=\""+p1Value+"\" class=\"inp\">"
+"<input type=\"text\" name=\""+p2+"\" size=\"16\" value=\""+p2Value+"\" class=\"inp\">";
out.print(outs);
}catch(Exception e){
e.printStackTrace();
}
return super.SKIP_BODY;
}
}
<%@ page contentType="text/html;charset=GB2312" %>
<%@ taglib uri="/WEB-INF/tld/struts-html.tld" prefix="html" %>
<%@ taglib uri="/WEB-INF/tld/mytags.tld" prefix="mytags"%>
<HTML>
<HEAD>
<TITLE>Some tags</TITLE>
</HEAD>
<body>
<html:form action="TestTagsAction">
<mytags:fourinputs p1="id1" p2="id2" />
<html:submit property="submit" />
</html:form>
</body>
</HTML>
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import org.apache.struts.taglib.html.Constants;
import org.apache.struts.util.RequestUtils;
public class TwoInputsTag extends BodyTagSupport {
private String p1;
private String p2;
public String getP1() {
return p1 ;
}
public void setP1(String p1) {
this.p1 = p1;
}
public String getP2() {
return p2;
}
public void setP2(String p2) {
this.p2 = p2;
}
public int doStartTag() throws JspException{
JspWriter out = pageContext.getOut();
try{
Object p1Obj = RequestUtils.lookup(super.pageContext, Constants.BEAN_KEY,p1,null) ;
Object p2Obj = RequestUtils.lookup(super.pageContext, Constants.BEAN_KEY,p2,null) ;
String p1Value = p1Obj == null ? "" :(String)p1Obj ;
String p2Value = p2Obj == null ? "" :(String)p2Obj ;
String outs =
"<input type=\"text\" name=\""+p1+"\" size=\"16\" value=\""+p1Value+"\" class=\"inp\">"
+"<input type=\"text\" name=\""+p2+"\" size=\"16\" value=\""+p2Value+"\" class=\"inp\">";
out.print(outs);
}catch(Exception e){
e.printStackTrace();
}
return super.SKIP_BODY;
}
}
//JSP:
<%@ page contentType="text/html;charset=GB2312" %>
<%@ taglib uri="/WEB-INF/tld/struts-html.tld" prefix="html" %>
<%@ taglib uri="/WEB-INF/tld/mytags.tld" prefix="mytags"%>
<HTML>
<HEAD>
<TITLE>Some tags</TITLE>
</HEAD>
<body>
<html:form action="TestTagsAction">
<mytags:fourinputs p1="id1" p2="id2" />
<html:submit property="submit" />
</html:form>
</body>
</HTML>
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