1.jsp标签2

设置y标签的代码

ying.tld

	<?xml version="1.0" encoding="UTF-8" ?><taglib xmlns="http://java.sun.com/xml/ns/j2ee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"version="2.0"><description>JSTL 1.1 core library</description><display-name>JSTL core</display-name><tlib-version>1.1</tlib-version><short-name>y</short-name><uri>/ying</uri><tag><name>demo</name><tag-class>com.yinbangchi.jspTag.DemoTag</tag-class><body-content>JSP</body-content></tag><tag><name>out</name><tag-class>com.yinbangchi.jspTag.OutTag</tag-class><body-content>empty</body-content><attribute><name>value</name><required>true</required><rtexprvalue>true</rtexprvalue></attribute> </tag><tag><name>if</name><tag-class>com.yinbangchi.jspTag.IFTag</tag-class><body-content>JSP</body-content> <attribute><name>test</name><required>true</required><rtexprvalue>true</rtexprvalue></attribute> </tag><tag><name>forEach</name><tag-class>com.yinbangchi.jspTag.ForEachTag</tag-class><body-content>JSP</body-content> <attribute><name>items</name><required>false</required><rtexprvalue>true</rtexprvalue></attribute> <attribute><name>var</name><required>true</required><rtexprvalue>false</rtexprvalue></attribute> <attribute><name>varStatus</name><required>false</required><rtexprvalue>false</rtexprvalue></attribute></tag><tag><name>set</name><tag-class>com.yinbangchi.jspTag.SetTag</tag-class><body-content>empty</body-content><attribute><name>value</name><required>true</required><rtexprvalue>false</rtexprvalue></attribute> </tag><tag><name>select</name><tag-class>com.yinbangchi.jspTag.SelectTag</tag-class><body-content>empty</body-content><attribute><name>items</name><required>true</required><rtexprvalue>true</rtexprvalue></attribute> <attribute><name>valueKey</name><required>true</required><rtexprvalue>false</rtexprvalue></attribute> <attribute><name>textKey</name><required>true</required><rtexprvalue>false</rtexprvalue></attribute><attribute><name>cssStyle</name><required>false</required><rtexprvalue>false</rtexprvalue></attribute><attribute><name>headKey</name><required>false</required><rtexprvalue>false</rtexprvalue></attribute><attribute><name>headValue</name><required>false</required><rtexprvalue>false</rtexprvalue></attribute><attribute><name>selectedOptionValu</name><required>false</required><rtexprvalue>false</rtexprvalue></attribute></tag></taglib>OutTagpackage com.yinbangchi.jspTag;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.tagext.BodyTagSupport;public class OutTag extends BodyTagSupport {private Object value;public OutTag() {}public Object getValue() {return value;}public void setValue(Object value) {this.value = value;}@Overridepublic int doStartTag() throws JspException {JspWriter out = pageContext.getOut();try {out.print(value==null?"":value.toString());} catch (Exception e) {// TODO: handle exceptionthrow new RuntimeException(e);}return super.doStartTag();}}

IfTag

		package com.yinbangchi.jspTag;import javax.servlet.jsp.JspException;import javax.servlet.jsp.tagext.BodyTagSupport;public class IFTag extends BodyTagSupport {private Boolean test;public IFTag() {}public Boolean getTest() {return test;}public void setTest(Boolean test) {this.test = test;}@Overridepublic int doStartTag() throws JspException {if(test) {return EVAL_BODY_INCLUDE;}return SKIP_BODY;}}

SetTag
package com.yinbangchi.jspTag;

		import javax.servlet.jsp.JspException;import javax.servlet.jsp.tagext.BodyTagSupport;public class IFTag extends BodyTagSupport {private Boolean test;public IFTag() {}public Boolean getTest() {return test;}public void setTest(Boolean test) {this.test = test;}@Overridepublic int doStartTag() throws JspException {if(test) {return EVAL_BODY_INCLUDE;}return SKIP_BODY;}}

SelectTag

		package com.yinbangchi.jspTag;import java.lang.reflect.InvocationTargetException;import java.util.List;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.tagext.BodyTagSupport;import org.apache.commons.beanutils.PropertyUtils;public class SelectTag extends BodyTagSupport {private List<Object> items;private String name;private String valueKey;private String textKey;private String cssStyle;private String headKey;private String headValue;private String selectedOptionValu;public String getSelectedOptionValu() {return selectedOptionValu;}public void setSelectedOptionValu(String selectedOptionValu) {this.selectedOptionValu = selectedOptionValu;}public SelectTag() {super();// TODO Auto-generated constructor stub}public List<Object> getItems() {return items;}public void setItems(List<Object> items) {this.items = items;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getValueKey() {return valueKey;}public void setValueKey(String valueKey) {this.valueKey = valueKey;}public String getTextKey() {return textKey;}public void setTextKey(String textKey) {this.textKey = textKey;}public String getCssStyle() {return cssStyle;}public void setCssStyle(String cssStyle) {this.cssStyle = cssStyle;}public String getHeadKey() {return headKey;}public void setHeadKey(String headKey) {this.headKey = headKey;}public String getHeadValue() {return headValue;}public void setHeadValue(String headValue) {this.headValue = headValue;}@Overridepublic int doStartTag() throws JspException {JspWriter out = pageContext.getOut();try {String html = toHtml();System.out.println(html);out.println(html);} catch (Exception e) {throw new RuntimeException(e);}return super.doStartTag();}private String toHtml() throws Exception{StringBuffer  sb=new StringBuffer();//<select name="" style="">sb.append("<select name='"+name+"'");sb.append("style='"+cssStyle+"'");sb.append(">");if(null!=items&&0!=items.size()) {if(null!=headKey&&!"".equals(headKey.trim())) {sb.append("<option value='"+headKey+"'>"+headValue+"</option>");}Object value=null;Object text=null;for (Object object : items) {value=PropertyUtils.getProperty(object, valueKey);text=PropertyUtils.getProperty(object, textKey);if(value.toString().equals(selectedOptionValu.trim())) {sb.append("<option selected value='"+value+"'>"+text+"</option>");}else {sb.append("<option value='"+value+"'>"+text+"</option>");}} }sb.append("</select>");//<option value="3">东北</option>return sb.toString();}}SelectTagpackage com.yinbangchi.jspTag;import java.lang.reflect.InvocationTargetException;import java.util.List;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.tagext.BodyTagSupport;import org.apache.commons.beanutils.PropertyUtils;public class SelectTag extends BodyTagSupport {private List<Object> items;private String name;private String valueKey;private String textKey;private String cssStyle;private String headKey;private String headValue;private String selectedOptionValu;public String getSelectedOptionValu() {return selectedOptionValu;}public void setSelectedOptionValu(String selectedOptionValu) {this.selectedOptionValu = selectedOptionValu;}public SelectTag() {super();// TODO Auto-generated constructor stub}public List<Object> getItems() {return items;}public void setItems(List<Object> items) {this.items = items;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getValueKey() {return valueKey;}public void setValueKey(String valueKey) {this.valueKey = valueKey;}public String getTextKey() {return textKey;}public void setTextKey(String textKey) {this.textKey = textKey;}public String getCssStyle() {return cssStyle;}public void setCssStyle(String cssStyle) {this.cssStyle = cssStyle;}public String getHeadKey() {return headKey;}public void setHeadKey(String headKey) {this.headKey = headKey;}public String getHeadValue() {return headValue;}public void setHeadValue(String headValue) {this.headValue = headValue;}@Overridepublic int doStartTag() throws JspException {JspWriter out = pageContext.getOut();try {String html = toHtml();System.out.println(html);out.println(html);} catch (Exception e) {throw new RuntimeException(e);}return super.doStartTag();}private String toHtml() throws Exception{StringBuffer  sb=new StringBuffer();//<select name="" style="">sb.append("<select name='"+name+"'");sb.append("style='"+cssStyle+"'");sb.append(">");if(null!=items&&0!=items.size()) {if(null!=headKey&&!"".equals(headKey.trim())) {sb.append("<option value='"+headKey+"'>"+headValue+"</option>");}Object value=null;Object text=null;for (Object object : items) {value=PropertyUtils.getProperty(object, valueKey);text=PropertyUtils.getProperty(object, textKey);if(value.toString().equals(selectedOptionValu.trim())) {sb.append("<option selected value='"+value+"'>"+text+"</option>");}else {sb.append("<option value='"+value+"'>"+text+"</option>");}} }sb.append("</select>");//<option value="3">东北</option>return sb.toString();}}

总结：可以