EntityCollection return if FetchXML (AGGREGATE SUM) Query didn't find anything 是什么意思？
What does EntityCollection return if FetchXML (AGGREGATE SUM) Query didn't find anything?
我是 运行 FetchXML 查询（聚合='true' 用于提取，聚合='sum' 用于所有属性）并在我的 C# 插件代码中将其传递给 RetreiveMultiple。如果 Fetchxml 没有找到任何东西怎么办，在这种情况下 service.RetrieveMultiple 检索什么？ 在调试器中，出现 NullReference 异常。
FetchXML 生成器 returns 这个：
我需要处理合同行中的一顿饭丢失的情况...在我的插件中，我有三个 Fetchxml 表达式，它们从合同行实体中检索数据（一天中的每顿饭，上午 SNACKS/LUNCH/PM 零食）。如果其中一个 FetchXML 实体没有要检索的数据，则该插件根本不会产生任何东西......即使其中一个 FetchXML 查询返回了一些结果......我只是想在没有数据返回时放置零三个 FETCHXML 查询中的任何一个... 请注意，如果我在合同行中包括所有三餐，插件工作正常！这是我的代码：
try
{
//Get Contract StartDate
DateTime startDate = (DateTime)PreImage["activeon"];
//Get Contract EndDate
DateTime endDate = (DateTime)PreImage["expireson"];
//Create an instance of the range class
Eachday range = new Eachday();
//use Weekday method of range class to get a weekdays list
var weekdays = range.WeekDay(startDate, endDate);
//Get Contract Number
string contractNumber = (string)PreImage["contractnumber"];
//Get Unit Order Lookup Id
EntityReference unitOrder = (EntityReference)PreImage.Attributes["new_unitorderid"];
var unitOrderId = unitOrder.Id;
//Query and aggregate each Weekday's order for the 3 different meal times...
//AM SNACK FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_am = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_amsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_amsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_amsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_amsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_amsum' aggregate='sum' />
<filter type='and' >
<condition value='100000001' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_am_result =
service.RetrieveMultiple(new FetchExpression(unitsum_am));
//AM SNACKS list for the week
var am_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the am_list
if (unitsum_am_result.Entities.Count == 0)
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_am_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_amsum"]).Value);
am_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_amsum"]).Value);
am_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_amsum"]).Value);
am_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_amsum"]).Value);
am_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_amsum"]).Value);
am_list.Add(fridaysum);
}
}
//LUNCH FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_lunch = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_lunchsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_lunchsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_lunchsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_lunchsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_lunchsum' aggregate='sum' />
<filter type='and' >
<condition value='100000002' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_lunch_result =
service.RetrieveMultiple(new FetchExpression(unitsum_lunch));
//Lunch meals list for the week
var lunch_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the lunch_list
if (unitsum_lunch_result.Entities.Count == 0)
{
lunch_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_lunch_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_lunchsum"]).Value);
lunch_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_lunchsum"]).Value);
lunch_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_lunchsum"]).Value);
lunch_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_lunchsum"]).Value);
lunch_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_lunchsum"]).Value);
lunch_list.Add(fridaysum);
}
}
//PM SNACK FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_pm = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_pmsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_pmsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_pmsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_pmsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_pmsum' aggregate='sum' />
<filter type='and' >
<condition value='100000003' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_pm_result =
service.RetrieveMultiple(new FetchExpression(unitsum_pm));
//PM SNACK list for the week
var pm_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the pm_list
if (unitsum_pm_result.Entities.Count == 0)
{
pm_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_pm_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_pmsum"]).Value);
pm_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_pmsum"]).Value);
pm_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_pmsum"]).Value);
pm_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_pmsum"]).Value);
pm_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_pmsum"]).Value);
pm_list.Add(fridaysum);
}
}
//iterate through entire contract duration
foreach(var day in weekdays)
{
Entity alterunit = new Entity("new_alterunitorder"); //create new alter unit record
alterunit.Attributes.Add("new_orderdate", DateTime.Parse(day)); //set the day field
var currentday = day.Split(',')[0]; //current day
switch (currentday)
{
case "Monday":
alterunit.Attributes.Add("new_amsnack", am_list[0]); //set the total am snacks
alterunit.Attributes.Add("new_lunch", lunch_list[0]); //set the total lunch meals
alterunit.Attributes.Add("new_pmsnack", pm_list[0]); //set the total pm snacks
break;
case "Tuesday":
alterunit.Attributes.Add("new_amsnack", am_list[1]);
alterunit.Attributes.Add("new_lunch", lunch_list[1]);
alterunit.Attributes.Add("new_pmsnack", pm_list[1]);
break;
case "Wednesday":
alterunit.Attributes.Add("new_amsnack", am_list[2]);
alterunit.Attributes.Add("new_lunch", lunch_list[2]);
alterunit.Attributes.Add("new_pmsnack", pm_list[2]);
break;
case "Thursday":
alterunit.Attributes.Add("new_amsnack", am_list[3]);
alterunit.Attributes.Add("new_lunch", lunch_list[3]);
alterunit.Attributes.Add("new_pmsnack", pm_list[3]);
break;
case "Friday":
alterunit.Attributes.Add("new_amsnack", am_list[4]);
alterunit.Attributes.Add("new_lunch", lunch_list[4]);
alterunit.Attributes.Add("new_pmsnack", pm_list[4]);
break;
default:
Console.WriteLine($"An unexpected value ({currentday})");
break;
}
alterunit.Attributes.Add("new_name", contractNumber); //set the record name
//set the unit order record relation
alterunit.Attributes["new_orderlineid"] =
new EntityReference("new_units", unitOrderId);
service.Create(alterunit); //create the record
}
}
调试结果如下：
190行也抛出异常：
它将 return 一个完全合格的 EntityCollection，但是 Entities 属性 在集合中将有零条记录。
既不为空也不为空。
您可以使用以下代码段来识别结果集：
if (unitsum_am_result.Entities.Count == 0)
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
//foreach....
}
实体集合实际上 return 是一个完全合格的 EntityCollection，实体计数将为零。但是，似乎在使用聚合 'sum' 时，如果集合为空，平台会抛出错误。 'count' 不会发生这种情况。为了修复它，我做了：
//iterate through all records and get the sum for each day
//place the sums into the am_list
foreach(var unit in unitsum_am_result.Entities)
{
try
{
am_list.Add(((int)((AliasedValue)unit["new_mondayunits_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_tuesdayunits_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitswednesday_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitsthursday_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitsfriday_amsum"]).Value));
}
catch
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
}
我是 运行 FetchXML 查询（聚合='true' 用于提取，聚合='sum' 用于所有属性）并在我的 C# 插件代码中将其传递给 RetreiveMultiple。如果 Fetchxml 没有找到任何东西怎么办，在这种情况下 service.RetrieveMultiple 检索什么？ 在调试器中，出现 NullReference 异常。
FetchXML 生成器 returns 这个：
我需要处理合同行中的一顿饭丢失的情况...在我的插件中，我有三个 Fetchxml 表达式，它们从合同行实体中检索数据（一天中的每顿饭，上午 SNACKS/LUNCH/PM 零食）。如果其中一个 FetchXML 实体没有要检索的数据，则该插件根本不会产生任何东西......即使其中一个 FetchXML 查询返回了一些结果......我只是想在没有数据返回时放置零三个 FETCHXML 查询中的任何一个... 请注意，如果我在合同行中包括所有三餐，插件工作正常！这是我的代码：
try
{
//Get Contract StartDate
DateTime startDate = (DateTime)PreImage["activeon"];
//Get Contract EndDate
DateTime endDate = (DateTime)PreImage["expireson"];
//Create an instance of the range class
Eachday range = new Eachday();
//use Weekday method of range class to get a weekdays list
var weekdays = range.WeekDay(startDate, endDate);
//Get Contract Number
string contractNumber = (string)PreImage["contractnumber"];
//Get Unit Order Lookup Id
EntityReference unitOrder = (EntityReference)PreImage.Attributes["new_unitorderid"];
var unitOrderId = unitOrder.Id;
//Query and aggregate each Weekday's order for the 3 different meal times...
//AM SNACK FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_am = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_amsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_amsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_amsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_amsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_amsum' aggregate='sum' />
<filter type='and' >
<condition value='100000001' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_am_result =
service.RetrieveMultiple(new FetchExpression(unitsum_am));
//AM SNACKS list for the week
var am_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the am_list
if (unitsum_am_result.Entities.Count == 0)
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_am_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_amsum"]).Value);
am_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_amsum"]).Value);
am_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_amsum"]).Value);
am_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_amsum"]).Value);
am_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_amsum"]).Value);
am_list.Add(fridaysum);
}
}
//LUNCH FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_lunch = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_lunchsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_lunchsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_lunchsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_lunchsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_lunchsum' aggregate='sum' />
<filter type='and' >
<condition value='100000002' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_lunch_result =
service.RetrieveMultiple(new FetchExpression(unitsum_lunch));
//Lunch meals list for the week
var lunch_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the lunch_list
if (unitsum_lunch_result.Entities.Count == 0)
{
lunch_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_lunch_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_lunchsum"]).Value);
lunch_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_lunchsum"]).Value);
lunch_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_lunchsum"]).Value);
lunch_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_lunchsum"]).Value);
lunch_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_lunchsum"]).Value);
lunch_list.Add(fridaysum);
}
}
//PM SNACK FetchXML Query.. string is passed to service.RetrieveMultiple();
string unitsum_pm = @" <fetch aggregate='true' distinct='false' >
<entity name='contract' >
<link-entity name='contractdetail' from = 'contractid' to = 'contractid' >
<attribute name='new_mondayunits' alias='new_mondayunits_pmsum' aggregate='sum' />
<attribute name='new_tuesdayunits' alias='new_tuesdayunits_pmsum' aggregate='sum' />
<attribute name='new_unitswednesday' alias='new_unitswednesday_pmsum' aggregate='sum' />
<attribute name='new_unitsthursday' alias='new_unitsthursday_pmsum' aggregate='sum' />
<attribute name='new_unitsfriday' alias='new_unitsfriday_pmsum' aggregate='sum' />
<filter type='and' >
<condition value='100000003' attribute='new_servingtime' operator= 'eq' />
<condition value='0' attribute='statecode' operator= 'eq' />
<condition value='" + targetId + @"' attribute='contractid' operator= 'eq' />
</filter >
</link-entity>
</entity >
</fetch>";
//Retrieve a collection of records
EntityCollection unitsum_pm_result =
service.RetrieveMultiple(new FetchExpression(unitsum_pm));
//PM SNACK list for the week
var pm_list = new List<int>();
//iterate through all records and get the sum for each day
//place the sums into the pm_list
if (unitsum_pm_result.Entities.Count == 0)
{
pm_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
foreach (var unit in unitsum_pm_result.Entities)
{
var mondaysum = ((int)((AliasedValue)unit["new_mondayunits_pmsum"]).Value);
pm_list.Add(mondaysum);
var tuesdaysum = ((int)((AliasedValue)unit["new_tuesdayunits_pmsum"]).Value);
pm_list.Add(tuesdaysum);
var wednesdaysum = ((int)((AliasedValue)unit["new_unitswednesday_pmsum"]).Value);
pm_list.Add(wednesdaysum);
var thursdaysum = ((int)((AliasedValue)unit["new_unitsthursday_pmsum"]).Value);
pm_list.Add(thursdaysum);
var fridaysum = ((int)((AliasedValue)unit["new_unitsfriday_pmsum"]).Value);
pm_list.Add(fridaysum);
}
}
//iterate through entire contract duration
foreach(var day in weekdays)
{
Entity alterunit = new Entity("new_alterunitorder"); //create new alter unit record
alterunit.Attributes.Add("new_orderdate", DateTime.Parse(day)); //set the day field
var currentday = day.Split(',')[0]; //current day
switch (currentday)
{
case "Monday":
alterunit.Attributes.Add("new_amsnack", am_list[0]); //set the total am snacks
alterunit.Attributes.Add("new_lunch", lunch_list[0]); //set the total lunch meals
alterunit.Attributes.Add("new_pmsnack", pm_list[0]); //set the total pm snacks
break;
case "Tuesday":
alterunit.Attributes.Add("new_amsnack", am_list[1]);
alterunit.Attributes.Add("new_lunch", lunch_list[1]);
alterunit.Attributes.Add("new_pmsnack", pm_list[1]);
break;
case "Wednesday":
alterunit.Attributes.Add("new_amsnack", am_list[2]);
alterunit.Attributes.Add("new_lunch", lunch_list[2]);
alterunit.Attributes.Add("new_pmsnack", pm_list[2]);
break;
case "Thursday":
alterunit.Attributes.Add("new_amsnack", am_list[3]);
alterunit.Attributes.Add("new_lunch", lunch_list[3]);
alterunit.Attributes.Add("new_pmsnack", pm_list[3]);
break;
case "Friday":
alterunit.Attributes.Add("new_amsnack", am_list[4]);
alterunit.Attributes.Add("new_lunch", lunch_list[4]);
alterunit.Attributes.Add("new_pmsnack", pm_list[4]);
break;
default:
Console.WriteLine($"An unexpected value ({currentday})");
break;
}
alterunit.Attributes.Add("new_name", contractNumber); //set the record name
//set the unit order record relation
alterunit.Attributes["new_orderlineid"] =
new EntityReference("new_units", unitOrderId);
service.Create(alterunit); //create the record
}
}
调试结果如下：
190行也抛出异常：
它将 return 一个完全合格的 EntityCollection，但是 Entities 属性 在集合中将有零条记录。
既不为空也不为空。
您可以使用以下代码段来识别结果集：
if (unitsum_am_result.Entities.Count == 0)
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
else
{
//foreach....
}
实体集合实际上 return 是一个完全合格的 EntityCollection，实体计数将为零。但是，似乎在使用聚合 'sum' 时，如果集合为空，平台会抛出错误。 'count' 不会发生这种情况。为了修复它，我做了：
//iterate through all records and get the sum for each day
//place the sums into the am_list
foreach(var unit in unitsum_am_result.Entities)
{
try
{
am_list.Add(((int)((AliasedValue)unit["new_mondayunits_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_tuesdayunits_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitswednesday_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitsthursday_amsum"]).Value));
am_list.Add(((int)((AliasedValue)unit["new_unitsfriday_amsum"]).Value));
}
catch
{
am_list.AddRange(Enumerable.Repeat(0, 5));
}
}