有的时候我们往往会遇到此种类似的需求:用户在访问某个详细的记录时,需要记录一下什么时候哪个用户访问过此页面,也就是说进入此页面时,需要插入一条记录到表中,表有用户信息,record id,sObject name以及vf page name.但是对于salesforce,不允许在controller的构造函数中进行DML操作,此种情况推荐采用两种方式实现此功能:
一.使用apex:page的action属性
1. DetailGoodsUseAjaxToolkitController:实现数据的初始化以及提供方法实现log记录的插入操作
1 public with sharing class DetailGoodsUseAjaxToolkitController {
2
3 public DetailGoodsUseAjaxToolkitController() {
4 initData();
5 }
6
7 private Map<String,String> params;
8
9 public Goods__c goods{get;set;}
10
11 private void initData() {
12 params = ApexPages.currentPage().getParameters();
13 String goodsId = params.get('id');
14 goods = [SELECT Goods_Code_Unique__c, GoodsBrand__c, GoodsCostPrice__c, GoodsDescribe__c,
15 GoodsName__c, GoodsPrice__c, GoodsProfit__c,Id FROM Goods__c
16 where id=:goodsId];
17 }
18
19
20 /*
21 * 用于apex:page绑定的action,执行完构造函数以后执行此方法
22 */
23 public void createLog() {
24 Log_Info__c log = new Log_Info__c();
25 log.Access_Date__c = system.now();
26 PageReference pr = ApexPages.currentPage();
27 String relatedURL = pr.getUrl();
28 Integer startIndex = relatedURL.lastIndexOf('/') + 1;
29 Integer endIndex = relatedURL.indexOf('?') == -1 ? relatedURL.length() : relatedURL.indexOf('?');
30 String pageName = relatedURL.substring(startIndex,endIndex);
31 log.Access_Page__c = pageName;
32 log.Accessor__c = UserInfo.getUserId();
33 insert log;
34 }
35 }
2.DetailGoodsUseAction.page:实现页面绘画以及通过action调用后台方法实现DML操作
1 <apex:page controller="DetailGoodsUseAjaxToolkitController" action="{!createLog}">
2 <apex:form >
3 <apex:pageBlock title="Goods Information">
4 <apex:pageBlockSection title="Goods Basic Information">
5 <apex:outputText id="GoodsUniqueCode" value="{!goods.Goods_Code_Unique__c}"/>
6 <apex:outputText id="GoodsName" value="{!goods.GoodsName__c}"/>
7 <apex:outputText id="GoodsPrice" value="{!goods.GoodsPrice__c}"/>
8 <apex:outputText id="GoodsCostPrice" value="{!goods.GoodsCostPrice__c}"/>
9 </apex:pageBlockSection>
10 </apex:pageBlock>
11 </apex:form>
12 </apex:page>
二.使用ajax toolkit
ajax toolkit API : https://resources.docs.salesforce.com/204/latest/en-us/sfdc/pdf/apex_ajax.pdf
相关核心API:https://developer.salesforce.com/docs/atlas.en-us.204.0.api.meta/api/sforce_api_calls_list.htm
ajax toolkit基于SOAP 的API,简单的说即通过js调用soap api实现少量的数据的页面展示或者对少量数据进行DML操作,如果对于大数据处理,别使用此种方式。
使用ajax toolkit主要三个步骤:
1.Connecting to the API :
针对非自定义button的引入
<apex:page>
<script src="../../soap/ajax/38.0/connection.js" type="text/javascript"></script>
<script>
sforce.connection.sessionId='{!GETSESSIONID()}';
...
</script>
...
</apex:page>
针对自定义onclick javascript按钮的引入:
<body>
{!requireScript("/soap/ajax/38.0/connection.js")} ...
2.Embedding API Calls in JavaScript :在javascript中嵌入API,然后通过回掉函数进行函数成功或者失败的处理操作;
3.Processing Results:对结果进行处理。 如果进行的是查询操作,可以对查询列表进行相关处理或者执行queryMore等操作,如果是进行DML操作可以判断是否执行成功等。
使用Ajax Toolkit可以实现同步或者异步的调用,详情参看上方PDF。
官方demo如下:
1 <apex:page >
2 <script type="text/javascript">
3 var __sfdcSessionId = '{!GETSESSIONID()}';
4 </script>
5 <script src="../../soap/ajax/38.0/connection.js" type="text/javascript"></script>
6 <script type="text/javascript">
7 window.onload = setupPage;
8 function setupPage() { //function contains all code to execute after page is rendered
9 var state = { //state that you need when the callback is called
10 output : document.getElementById("output"),
11 startTime : new Date().getTime()
12 };
13 var callback = { //call layoutResult if the request is successful
14 onSuccess: layoutResults, //call queryFailed if the api request fails
15 onFailure: queryFailed,
16 source: state
17 };
18 sforce.connection.query( "Select Id, Name, Industry From Account order by Industry", callback);
19 }
20
21 function queryFailed(error, source) {
22 source.output.innerHTML = "An error has occurred: " + error;
23 }
24 /** * This method will be called when the toolkit receives a successful
25 * response from the server.
26 * @queryResult - result that server returned
27 * @source - state passed into the query method call.
28 */
29 function layoutResults(queryResult, source) {
30 if (queryResult.size > 0) {
31 var output = ""; //get the records array
32 var records = queryResult.getArray('records'); //loop through the records and construct html string
33 for (var i = 0; i < records.length; i++) {
34 var account = records[i];
35 output += account.Id + " " + account.Name + " [Industry - " + account.Industry + "]<br>";
36 } //render the generated html string
37 source.output.innerHTML = output;
38 }
39 }
40 </script>
41
42 <div id="output"> </div>
43 </apex:page>
通过demo可以看出:通过api先进行query操作查出Industry表数据,然后进行callback回掉,callback执行success和error的相关处理从而实现数据的展示。
通过ajax toolkit实现log数据的插入
1 <apex:page controller="DetailGoodsUseAjaxToolkitController">
2 <apex:form >
3 <apex:pageBlock title="Goods Information">
4 <apex:pageBlockSection title="Goods Basic Information">
5 <apex:outputText id="GoodsUniqueCode" value="{!goods.Goods_Code_Unique__c}"/>
6 <apex:outputText id="GoodsName" value="{!goods.GoodsName__c}"/>
7 <apex:outputText id="GoodsPrice" value="{!goods.GoodsPrice__c}"/>
8 <apex:outputText id="GoodsCostPrice" value="{!goods.GoodsCostPrice__c}"/>
9 </apex:pageBlockSection>
10 </apex:pageBlock>
11 </apex:form>
12
13 <script type="text/javascript">
14 var __sfdcSessionId = '{!GETSESSIONID()}';
15 </script>
16 <script src="/soap/ajax/38.0/connection.js" type="text/javascript"></script>
17 <script src="/soap/ajax/38.0/apex.js" type="text/javascript"></script>
18 <script type="text/javascript">
19 window.onload = setupPage;
20 function setupPage() {
21 var logInfo = new sforce.SObject("Log_Info__c");
22 logInfo.Accessor__c = "{!$User.Id}";
23 var accessDate = new Date("{!NOW()}");
24 logInfo.Access_Date__c = accessDate;
25 logInfo.Access_Page__c = "{!$CurrentPage.Name}";
26 var result = sforce.connection.create([logInfo]);
27 if (result[0].getBoolean("success")) {
28 //do success process
29 } else {
30 //do error process
31 }
32 }
33 </script>
34 </apex:page>
此种方式运行效果:
1.Log_Info__c最开始没有任何数据
2.访问当前页面
3.访问页面后数据库便存储了一条当前访问者访问的页面的Log数据
注意:此种方式对于谷歌浏览器会有一个问题,使用谷歌浏览器访问会出现Refused to set unsafe header "User-Agent",解决方式可以为下载connection.js注释掉关于User-Agent的处理,然后上传到static resources中,在VF page引入static resource而不是系统的connection.js即可
总结:此种类似需求其实可以很多种方式实现,此处只是使用两种方式实现。第一种方式简单粗暴,而且兼容性好,第二种方式只是起到抛砖引玉的效果,关于ajax toolkit什么时候使用以及限制等请自行查看上方PDF。