Dynamic CRM 2013学习笔记（九）CrmFetchKit.js介绍：Fetchxml、多表联合查询, 批量更新

浏览数：157 / 时间：2015年06月09日

CrmFetchKit.js是一个跨浏览器的一个类库，允许通过JavaScript来执行fetch xml的查询，还可以实现批量更新，分页查询等。目前已支持Chrome 25， Firefox 19 和 IE9/10 .

它的最大优势是可以通过fetchxml 来查询，这样我们就可以实现真正的多表联合查询，虽然可以用OData终结点的$expand来进行多表的联合查询，但这种方式没办法过滤多表的条件，它只能过滤主表的条件。

下面来看下简单的多表查询的例子：

1.首先定义一个fetchxml：

  1: var fetchxml = [‘<fetch version="1.0" output-format="xml-platform" ‘,
  2:                     ‘mapping="logical" ‘,
  3:                     ‘returntotalrecordcount="true" >‘,
  4:                 ‘<entity name="new_floor_price">‘,
  5:                 ‘<attribute name="new_floor_priceid" />‘,
  6:                 ‘<order attribute="modifiedon" descending="true" />‘,
  7:                 ‘<filter type="and">‘,
  8:                     ‘<condition attribute="new_approval_status" operator="eq" value="3" />‘,
  9:                 ‘</filter>‘,
 10:                 ‘<link-entity name="new_fp_item" from="new_fp" to="new_floor_priceid" alias="ar">‘,
 11:                     ‘<attribute name="new_floor_price" />‘,
 12:                     ‘<filter type="and">‘,
 13:                     ‘<condition attribute="new_modelid" operator="eq" value="‘ + modelid + ‘" />‘,
 14:                     ‘</filter>‘,
 15:                 ‘</link-entity>‘,
 16:                 ‘</entity>‘,
 17:             ‘</fetch>‘].join(‘‘);

我一般先写好sql语句，然后在 http://sql2fetchxml.com/ 这里生成fetchxml 语句，再小改下参数就成了。

在上面的框里输入SQL 语句，点击中间的Convert，就可以在下面的框里生成 Fetchxml的语句。

2. 调用很简单：

  1: CrmFetchKit.Fetch(fetchxml).then(function (results) {
  2:         if(results!=null)
  3:             setAttributeValue("new_floor_price", Number(results[0].getValue("ar.new_floor_price")));
  4:     }, onFetchError);

3. 错误处理：

  1: function onFetchError(xhr, status, errorThrown) {
  2:     
  3:     var errormsg = $(xhr.responseXML).find(‘Message‘).text();
  4: 
  5:     alert(‘CrmFetchKit-Error occured: ‘ +  errormsg);
  6: }

4. 另一种写法：

  1: // execute the query (async)
  2: CrmFetchKit.Fetch(fetchxml)
  3:   .fail(function(xhr, status, errorThrown){ 
  4: 
  5:       // get the error-message
  6:       var msg = $(xhr.responseXML).find(‘Message‘).text();
  7: 
  8:       alert(‘Error occured: ‘ + msg);
  9:   })
 10:   .done(function(results){
 11:     
 12:       var contactid = null;
 13: 
 14:       for( var i = 0, max = results.length; i < max; i++) {
 15: 
 16:     contactid = results[i].getValue(‘contactid‘);
 17: 
 18:     // Assign (async)
 19:     CrmFetchKit.Assign(contactid, ‘contact‘, bId);
 20:       }
 21:   });

这个示例中，还介绍了CrmFetchKit.Assign的用法

CrmFetchKit.Assign(contactid, ‘contact‘, bId);

这样就可以实现批量更新了

5. FetchMore 用法

  1: var fetchxml = [‘<fetch version="1.0" output-format="xml-platform" ‘,
  2:                         ‘mapping="logical" ‘,
  3:                         ‘returntotalrecordcount="true" ‘,
  4:                         ‘count="10">‘,
  5:                 ‘ <entity name="contact">‘,
  6:                 ‘ <attribute name="lastname" />‘,
  7:                 ‘ <attribute name="contactid" />‘,
  8:                 ‘ <filter type="and">‘,
  9:                 ‘ <condition attribute="lastname" operator="like" value="test%" />‘,
 10:                 ‘ </filter>‘,
 11:                 ‘ </entity>‘,
 12:                 ‘</fetch>‘].join(‘‘);
 13: 
 14: CrmFetchKit.FetchMore(fetchxml).then(function (response) {
 15: 
 16:     // 获取实体名
 17:     var entityname = response.entityName;
 18: 
 19:     // fetchxml里必须设置 ‘returntotalrecordcount="true" ‘ 
 20:     var total = response.moreRecords;
 21: 
 22:     // 取得实体的数组
 23:     var set = response.entities;
 24: 
 25:     // 分页就需要这个 page-cookie
 26:     var pageCookie = response.pagingCookie;
 27:     
 28:     ...
 29: 
 30: }, onFetchError);

6. FetchAll用法：

  1: var fetchxml = [‘<fetch version="1.0" output-format="xml-platform" ‘,
  2:                         ‘mapping="logical" ‘,
  3:                         ‘count="10">‘,
  4:                 ‘ <entity name="contact">‘,
  5:                 ‘ <attribute name="lastname" />‘,
  6:                 ‘ <attribute name="contactid" />‘,
  7:                 ‘ <filter type="and">‘,
  8:                 ‘ <condition attribute="lastname" operator="like" value="test%" />‘,
  9:                 ‘ </filter>‘,
 10:                 ‘ </entity>‘,
 11:                 ‘</fetch>‘].join(‘‘);
 12: 
 13: CrmFetchKit.FetchAll(fetchxml).then(function (entities) {
 14: 
 15:     /* success-handler */
 16: 
 17: }, onFetchError);