Requirements: Click the drop-down option box, select a data type, and automatically display the names of all data items under this type in the form, that is, all unique ddlNames corresponding to the same keyword in the database.
<script type="text/javascript" src="${pageContext.request.contextPath }/script/pub.js?1.1.11"></script>
function changetype(){
if(document.Form1.keyword.value=="jerrynew"){
var textStr="<input type=\"text\" name=\"keywordname\" maxlength=\"50\" size=\"24\"> ";
document.getElementById("newtypename").innerHTML="类型名称：";
document.getElementById("newddlText").innerHTML=textStr;
Pub.submitActionWithForm('Form2','${pageContext.request.contextPath }/system/elecSystemDDLAction_edit.do','Form1');
}else{ var textStr="";
document.getElementById("newtypename").innerHTML="";
document.getElementById("newddlText").innerHTML=textStr; /**
* 参数一：传递dictionaryIndex.jsp的From2的表单
* 参数二：传递URL路径地址
* 参数三：传递dictionaryIndex.jsp的From1的表单
原理：使用Ajax
* 传递dictionaryIndex.jsp中表单Form1中的所有元素作为参数，传递给服务器，并在服务器进行处理
* 将处理后的结果放置到dictionaryEdit.jsp中
* 将dictionaryEdit.jsp页面的全部内容放置到dictionaryIndex.jsp表单Form2中*/Pub.submitActionWithForm('Form2','${pageContext.request.contextPath }/system/elecSystemDDLAction_edit.do','Form1');
}
}Where submitActionWithForm Methods are defined in pub.js.
3. Define 5 methods in pub.js: (1) Pub.submitActionWithForm method/***
* domId：表单Form2的名称
* action：表示URL连接
* sForm：表单Form1的名称 */Pub.submitActionWithForm=function(domId,action,sForm){ /**第一步：创建Ajax引擎对象*/
var req = Pub.newXMLHttpRequest(); /**第二步：req.onreadystatechange表示事件处理函数（相当于一个监听），用来监听客户端与服务器端的连接状态*/
var handlerFunction = Pub.getReadyStateHandler(req, domId,Pub.handleResponse);
req.onreadystatechange = handlerFunction; /**第三步：打开一个连接，要求：如果是POST请求，需要设置一个头部信息，否则此时不能使用req.send()方法向服务器发送数据*/
req.open("POST", action, true);
req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
/**第四步：向服务器发送数据，格式：name=张三&age=28*/
var str = Pub.getParams2Str(sForm);
//传递表单Form1中的元素作为参数给服务器 req.send(str);
}/**
* 用于创建ajax引擎 */Pub.newXMLHttpRequest=function newXMLHttpRequest() { var xmlreq = false; if (window.XMLHttpRequest) {xmlreq = new XMLHttpRequest();
} else if (window.ActiveXObject) { try {
xmlreq = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e1) {
try {
xmlreq = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e2) {
alert(e2);
}
}
} return xmlreq;
}xmlreq = new XMLHttpRequest() is the core object of Ajax operation
/**
* @Description:传递表单Form1中的元素作为参数
* @param sForm：传递表单Form1的名称
* @returns {String}：使用ajax返回服务器端的参数，传递的就是表单Form1中元素的参数 */Pub.getParams2Str=function getParams2Str(sForm){ var strDiv="";
try {var objForm=document.forms[sForm]; if (!objForm)return strDiv; var elt,sName,sValue; for (var fld = 0; fld < objForm.elements.length; fld++) {
elt = objForm.elements[fld];
sName=elt.name;
sValue=""+elt.value; if(fld==objForm.elements.length-1)
strDiv=strDiv + sName+"="+sValue+""; else
strDiv=strDiv + sName+"="+sValue+"&";
}
} catch (ex) {return strDiv;
}
return strDiv;
}= (req.readyState == 4 (req.status == 200"HTTP error: "+
/**
* @Description:将结果返回dictionaryEdit.jsp，并放置到dictionaryIndex.jsp的Form2中
* @param data：服务器返回的结果
* @param eleid：表单Form2的名称 */Pub.handleResponse= function handleResponse(data,eleid){ //获取表单Form2的对象 var ele =document.getElementById(eleid); //将返回的结果放置到表单Form2的元素中 ele.innerHTML = data;
}The next step is to operate the Action class. You need to query the corresponding ddlName in the database based on the keyword. Operation:
/**
* @Name: edit
* @Description: 跳转到数据字典编辑页面
* @Parameters: 无
* @Return: String：跳转到system/dictionaryEdit.jsp*/public String edit(){//1.获取数据类型String keyword = elecSystemDDL.getKeyword();//2.使用数据类型查询数据字典，返回List<ElecSystemDDL>List<ElecSystemDDL> list=elecSystemDDLService.findSystemDDLListByKeyword(keyword);
request.setAttribute("list", list);return "edit";
}List<ElecSystemDDL> findSystemDDLListByKeyword(String keyword);
/**
* @Name: findSystemDDLListByKeyword
* @Description: 根据数据类型名称查询数据字典
* @Parameters: keyword:数据类型名称
* @Return: List：存储ElecSystemDDL对象集合*/@Overridepublic List<ElecSystemDDL> findSystemDDLListByKeyword(String keyword) {//查询条件String condition="";//查询条件对应的参数List<Object> paramsList = new ArrayList<Object>();if(StringUtils.isNotBlank(keyword)){
condition=" and o.keyword=?";
paramsList.add(keyword);
}//传递可变参数Object[] params = paramsList.toArray();//排序Map<String, String> orderby = new LinkedHashMap<String, String>();
orderby.put("o.ddlCode", "asc");
List<ElecSystemDDL> list = elecSystemDDLDao.findCollectionByConditionNoPage(condition, params, orderby);return list;
}The findCollectionByConditionNoPage(condition, params, orderby) method is implemented by commonDao according to the specified Condition, method to return query result set (without paging)
7.dictionaryEdit.jsp traverses the value of the object<%@taglib uri="/struts-tags" prefix="s"%>
<s:if test="#request.list!=null && #request.list.size()>0">
<s:iterator value="#request.list">
<tr>
<td class="ta_01" align="center" width="20%"><s:property value="ddlCode"/></td>
<td class="ta_01" align="center" width="60%">
<input id="<s:property value="ddlCode"/>" name="itemname" type="text" value="<s:property value="ddlName"/>" size="45" maxlength="25"></td>
<td class="ta_01" align="center" width="20%">
<a href="#" onclick="delTableRow('<s:property value="ddlCode"/>')">
<img src="${pageContext.request.contextPath }/images/delete.gif" width="16" height="16" border="0" style="CURSOR:hand"></a>
</td>
</tr>
</s:iterator>
</s:if>
<s:else>
<tr>
<td class="ta_01" align="center" width="20%">1</td>
<td class="ta_01" align="center" width="60%">
<input name="itemname" type="text" size="45" maxlength="25">
</td>
<td class="ta_01" align="center" width="20%"></td>
</tr>
</s:else>Effect display:
Complete the selection type list and realize the content replacement of the Form2 form.
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