CRM 2011 Plugin 知识的总结加代码解释

1.??的使用,就是判断值是否为null,为null的话，给赋初值，否则就直接取值。

decimal new_amount = 0;

if (targetEntity.Contains("字段1"))
{
   //?? 判断(targetEntity["字段1"] as Money为null的话，赋值为0
   new_amount = (targetEntity["字段1"] as Money ?? new Money(0M)).Value;
}

注:字段1为货币（Money）类型。

2. 一般从Targt 中取值,必须先判断是否存在，然后在判断不为null.不然会报错，因为字段1有可能不在Target里面，意思

targetEntity.Contains("字段1")为False,那么直接写targetEntity["字段1"] != null，就会报错。不信，大家可以试试。 

decimal new_amount = 0;

if (targetEntity.Contains("字段1") && targetEntity["字段1"] != null)
{
    new_amount = (targetEntity["字段1"] as Money).Value;
}
而不能
if (targetEntity["字段1"] != null && targetEntity.Contains("字段1"))
{
    new_amount = (targetEntity["字段1"] as Money).Value;
}

注:字段1为货币（Money）类型。

3.可以将Entity取出的字段放在AttributeCollection 属性集合中去，然后可以直接从这个属性集合中取值。

/// <summary>
/// 获取属性集合
/// </summary>
/// <param name="dataEntity">Entity</param>
/// <returns>返回属性集合</returns>
public AttributeCollection GetTriggerData(Entity dataEntity)
{
    AttributeCollection parames = new AttributeCollection();

    if (dataEntity != null)
    {
        //先将字段放在一个字符串数组中
        string[] arrayStr = { "new_actiontype",
            "new_po_status", "new_sort",
            "new_detailitem","new_costfrom","new_bgcontrolperiod" };
        //foreache 循环判断，把dataEntity的索引赋给parames中去。
        foreach (var item in arrayStr)
        {
            if (dataEntity.Contains(item) && dataEntity[item] != null)
            {
                parames[item] = dataEntity[item];
            }
        }
    }
    return parames;
}
调用：AttributeCollection parmes = GetTriggerData(dataEntity);

4.根据很多条件，查询一个实体的实体集合，除了fetchxml,也可以用QueryByAttribute。

/// <summary>
/// 根据所属预算品类、费用项目、费用归属和预算控制期间获取预算费用项实体
/// </summary>
/// <param name="service">crm组织服务</param>
/// <param name="parmes">属性集合</param>
/// <returns>返回Entity</returns>
public Entity GetBugetByParmes(IOrganizationService service, AttributeCollection parmes)
{
    QueryByAttribute query = new QueryByAttribute("new_buget");查询的实体
    query.ColumnSet = new ColumnSet("new_bugetid");//查询的列
    query.AddAttributeValue("statecode", 0);//查询的条件
    query.AddAttributeValue("new_sort", (parmes["new_sort"] as EntityReference).Id);
    query.AddAttributeValue("new_expenseitem", (parmes["new_detailitem"] as EntityReference).Id);
    query.AddAttributeValue("new_bugetunit", (parmes["new_costfrom"] as EntityReference).Id);
    query.AddAttributeValue("new_bedgetsheet", (parmes["new_bgcontrolperiod"] as EntityReference).Id);

    EntityCollection acc_new_buget = service.RetrieveMultiple(query);

    Entity new_bugetEntity = null;

    if (acc_new_buget.Entities.Count > )
    {
        new_bugetEntity = acc_new_buget.Entities[] as Entity;
    }

    return new_bugetEntity;
}

5.Double? 类型+？ ?是表示值类型可以为null,值类型的初始化不为null，比如int的初始值为0.

具体可以参考msdn:http://msdn.microsoft.com/zh-cn/library/1t3y8s4s(v=vs.90).aspx

//查询
QueryByAttribute query = new QueryByAttribute("new_exp_undertaker");
query.ColumnSet = new ColumnSet("new_ratio_undertaker");
query.AddAttributeValue("new_pe_undertaker", new_promotion_peid);

EntityCollection accEntityColls = service.RetrieveMultiple(query);

if (accEntityColls.Entities.Count == ) return;

foreach (Entity accEntity in accEntityColls.Entities)
{
    Double? new_ratio_undertaker = accEntity.Contains("new_ratio_undertaker")
    ? accEntity["new_ratio_undertaker"] as Double? : new Double?();
    //更新
    UpdateNew_deficit(service, new_ratio_undertaker, new_writeoff, accEntity.Id);
}
取值：(decimal)((new_ratio_undertaker.Value)

6. 如果一个实体上其他字段汇总到另外字段上，比如字段a,b,c,d 需要d = a+b*c，当进行这样子操作的时候，只有Create和Update，而且都为Pre_validation操作，能放到

Pre_validation(10)处理，尽量放到Pre_validation处理，因为这样子性能比较好，至于具体原因可以看SDK。

还有一般做check,或者导入数据根据一个lookup字段的带出值，赋给另外一个字段，也可以放在这里处理。CRM4的话是context.Stage == 10，Pre前期处理。这里暂不说明。

Entity targetEntity = context.InputParameters["Target"] as Entity;

//消息名称
string messageName = context.MessageName;

decimal sumNew_budgetbalance = ;

switch (messageName)
{
    case "Create":
            sumNew_budgetbalance = DoCreateSumNew_budgetbalance(targetEntity);
            break;
    case "Update":
            sumNew_budgetbalance = DoUpdateSumNew_budgetbalance(targetEntity, preImageEntity);
            break;
}

targetEntity["new_budgetbalance"] = new Money(sumNew_budgetbalance);

context.InputParameters["Target"] = targetEntity;//把提交的值放到Target中，当保存之后，就会把这些值保存到数据库中。

}

.RegisterFile.crmregister:

 <Plugin Description="Plug-in to New_bugetUpdatenew_CalcuBudgetbalance" FriendlyName="New_bugetUpdatenew_CalcuBudgetbalance" Name="Frensworkz.LibyCrm.Plugins.New_bugetUpdatenew_CalcuBudgetbalance" Id="b5985a39-e284-e311-ad3b-00155d386b48" TypeName="Frensworkz.LibyCrm.Plugins.New_bugetUpdatenew_CalcuBudgetbalance">
          <Steps>
            <clear />
            <Step CustomConfiguration="" Name="New_bugetUpdatenew_CalcuBudgetbalance" Description="New_bugetUpdatenew_CalcuBudgetbalance Create" Id="b6985a39-e284-e311-ad3b-00155d386b48" MessageName="Create" Mode="Synchronous" PrimaryEntityName="new_buget" Rank="" SecureConfiguration="" Stage="PreOutsideTransaction" SupportedDeployment="ServerOnly">
              <Images />
            </Step>
            <Step CustomConfiguration="" Name="New_bugetUpdatenew_CalcuBudgetbalance" Description="New_bugetUpdatenew_CalcuBudgetbalance Update" Id="b9985a39-e284-e311-ad3b-00155d386b48" MessageName="Update" Mode="Synchronous" PrimaryEntityName="new_buget" Rank="" SecureConfiguration="" Stage="PreOutsideTransaction" SupportedDeployment="ServerOnly">
              <Images>
                <Image Attributes="new_quotabudget,new_ratio,new_saletarget,new_standardbuget,new_programholdbudget,new_noprogramhold,new_sales_app,new_pe_ch_money,new_po_ch_money,new_sales_release,new_adjust_fee,new_send_in,new_adjust_reduce" EntityAlias="PreImage" Id="bc985a39-e284-e311-ad3b-00155d386b48" MessagePropertyName="Target" ImageType="PreImage" />
              </Images>
            </Step>
          </Steps>
        </Plugin>

1

大家肯定会问，为什么会这样子写Plugin，这里暂不说明。

7.将明细中的金额汇总到主表上的一个字段时，很多人都没有考虑到SetStateDynamicEntity这个步骤。

base.RegisteredEvents.Add(new Tuple<int, string, string, Action<LocalPluginContext>>(, "Create", "new_po", new Action<LocalPluginContext>(ExecuteNew_po_New_po_status_SumNew_tt_budget)));
            base.RegisteredEvents.Add(new Tuple<int, string, string, Action<LocalPluginContext>>(, "Update", "new_po", new Action<LocalPluginContext>(ExecuteNew_po_New_po_status_SumNew_tt_budget)));
            base.RegisteredEvents.Add(new Tuple<int, string, string, Action<LocalPluginContext>>(, "Delete", "new_po", new Action<LocalPluginContext>(ExecuteNew_po_New_po_status_SumNew_tt_budget)));
            base.RegisteredEvents.Add(new Tuple<int, string, string, Action<LocalPluginContext>>(, "SetStateDynamicEntity", "new_po", new Action<LocalPluginContext>(ExecuteNew_po_New_po_status_SumNew_tt_budget)));

protected void ExecuteNew_po_New_po_status_SumNew_tt_budget(LocalPluginContext localContext)
{
if (localContext == null)
{
    throw new ArgumentNullException("localContext");
}

IPluginExecutionContext context = localContext.PluginExecutionContext;

IOrganizationService service = localContext.OrganizationServiceAll;

Entity dataEntity = null;
switch (context.MessageName)
{
    case "Create":
        dataEntity = context.InputParameters["Target"] as Entity;
        break;
    case "Update":
    case "SetStateDynamicEntity":
        dataEntity = context.PostEntityImages[this.postImageAlias] as Entity;
        break;
    case "Delete":
        dataEntity = context.PreEntityImages[this.preImageAlias] as Entity;
        break;
}

 New_po_New_po_status_SumNew_tt_budgetAction(service, dataEntity);

}

8.从DataRow中取值的时候，需要判断row["new_sort"].ToString()不能为空。

foreach (DataRow row in ds.Tables[].Rows)
{
  if (!string.IsNullOrEmpty(row["new_sort"].ToString()))
  {
     new_sort = new Guid(row["new_sort"].ToString());
  }
}

9.新建(Create)的时候，需要判断preImageEntity != null。

private readonly string preImageAlias = "image";
Entity preImageEntity = (context.PreEntityImages != null && context.PreEntityImages.Contains(this.preImageAlias)) ? context.PreEntityImages[this.preImageAlias] : null;

if(messageName =="Create")
{
 if(preImageEntity != null)
 {
   if(preImageEntity.Contains("new_promotion_pe"))
   {
     new_promotion_peId = (preImageEntity["new_promotion_pe"] as EntityReference).Id;
   }
 }
}