Check Entity and Attribute Exist in CRM or not?

   private bool DoesAttributeExist(string entityName,string attributeName, IOrganizationService service)
        {
            RetrieveEntityRequest request = new RetrieveEntityRequest
            {
                EntityFilters = Microsoft.Xrm.Sdk.Metadata.EntityFilters.Attributes,
                LogicalName = entityName
            };
            RetrieveEntityResponse response
              = (RetrieveEntityResponse)service.Execute(request);

            return response.EntityMetadata.Attributes.FirstOrDefault(element => element.LogicalName == attributeName && element.AttributeType.Value == AttributeTypeCode.DateTime) != null;
        }

        private bool DoesEntityExist(string entityName, IOrganizationService _service)
        {
            RetrieveAllEntitiesRequest allEntitiesRequest = new RetrieveAllEntitiesRequest();
            // Retrieve only the currently published changes, ignoring the changes that have
            // not been published.
            allEntitiesRequest.RetrieveAsIfPublished = false;
            //allEntitiesRequest.MetadataItems = MetadataItems.EntitiesOnly;

            // Execute the request
            RetrieveAllEntitiesResponse allEntitiesResponse = (RetrieveAllEntitiesResponse)_service.Execute(allEntitiesRequest);

            // Iterate through the retrieved entities
            foreach (EntityMetadata entity in allEntitiesResponse.EntityMetadata)
            {
                if (entity.LogicalName == entityName)
                    return true;
            }
            return false;
        }

How to use ExecuteMultipleRequest with ServiceContext and Linq

The following code is retrieving all the contacts where parent customer id is C6CB814A-BA75-E011-8720-00155DA5304E and updating their phone number.

var ServiceContext = new OrganizationServiceContext(service);
Guid accountid = new Guid("C6CB814A-BA75-E011-8720-00155DA5304E");

// Create an ExecuteMultipleRequest object.
ExecuteMultipleRequest requestWithResults = new ExecuteMultipleRequest()
{
    // Assign settings that define execution behavior: continue on error, don't return responses. 
    Settings = new ExecuteMultipleSettings()
    {
        ContinueOnError = false,
        ReturnResponses = false
    }, 
    // Create an empty organization request collection.
    Requests = new OrganizationRequestCollection()
};
               
requestWithResults.Requests.AddRange(from c in ServiceContext.CreateQuery("contact")
                                    where c["parentcustomerid"].Equals(accountid)
                                    select new UpdateRequest()
                                    {
                                        Target = new Entity("contact")
                                        {
                                            Id = c.Id,
                                            Attributes = { new KeyValuePair<string,object>("telephone1", "+61402234212") }
                                        }
                                    });

// Excute the requests
ExecuteMultipleResponse Response = (ExecuteMultipleResponse)service.Execute(requestWithResults);

Filtering records in the sub grid in Microsoft Dynamics CRM 2011 and CRM 2013

function updateSubGrid() {
debugger
    //This will get the related products grid details and store in a variable.

    var relatedProducts = document.getElementById("AllActivities");
    //Initializing the lookup field to store in an array.

    var lookupfield = new Array;



    //Get the lookup field

    lookupfield = Xrm.Page.getAttribute("to").getValue();



    //This will get the lookup field guid if there is value present in the lookup

    if (lookupfield != null) {

        var lookupid = lookupfield[0].id;

    }



    //Else the function will return and no code will be executed.

    else {

        return;

    }

     

    //This method is to ensure that grid is loaded before processing.

    if (relatedProducts ==null || relatedProducts.readyState != "complete")

    {



        //This statement is used to wait for 2 seconds and recall the function until the grid is loaded.

        setTimeout('updateSubGrid()', 2000);

        return;

    }  

    //This is the fetch xml code which will retrieve all the order products related to the order selected for the case.

    var fetchXml = "<fetch version='1.0' output-format='xml-platform' mapping='logical' distinct='false'>";

    fetchXml += "<entity name='activitypointer'>";

    fetchXml += "<attribute name='activitytypecode' />";

    fetchXml += "<attribute name='subject' />";

    fetchXml += "<attribute name='prioritycode' />";

    fetchXml += "<attribute name='activityid' />";

    fetchXml += "<attribute name='instancetypecode' />";

    fetchXml += "<attribute name='regardingobjectid' />";

fetchXml += "<attribute name='scheduledstart' />";

fetchXml += "<attribute name='scheduledend' />";

    fetchXml += "<filter type='and'>";

    fetchXml += "<condition attribute='salesorderid' operator='eq'  value='" + lookupid + "' />";

    fetchXml += "</filter>";

    fetchXml += "</entity>";

    fetchXml += "</fetch>";

     

    //Setting the fetch xml to the sub grid.

    relatedProducts.control.SetParameter("fetchXml", fetchXml);



    //This statement will refresh the sub grid after making all modifications.

    relatedProducts.control.refresh();

}   

Create View in CRM using coding.

 var fetchxml = "<fetch distinct='true' mapping='logical' output-format='xml-platform' version='1.0'><entity name='account'><attribute name='name'/><attribute name='primarycontactid'/><attribute name='telephone1'/><attribute name='accountid'/><order descending='false' attribute='name'/><link-entity name='incident' alias='ac' link-type='outer' to='accountid' from='customerid'/><filter type='and'><condition attribute='customerid' operator='null' entityname='incident'/><condition attribute='statecode' operator='eq' value='0'/></filter></entity></fetch>";

            var savedQuery = new SavedQuery()
            {
                Name = "Acount with no Cases",
                ReturnedTypeCode = "account",
                FetchXml = fetchxml,

                QueryType = 0
            };
            _service.Create(savedQuery);

How to get the Microsoft CRM “Closed Activities” Nav Bar Link Back (if you delete it)

Just export the solution of entity and add following relationship

<NavBarByRelationshipItem RelationshipName="Contact_ActivityPointers" Id="navActivityHistory" TitleResourceId="Tab_Label_History" Icon="/_imgs/ico_18_history.gif" ViewId="21E2B905-6FDB-470d-8517-AD69B4C01268" Sequence="20" Area="Info">
<Privileges>
     <Privilege Entity="" Privilege="ReadActivity" />
</Privileges>
<Titles>
<Title LCID="1033" Text="Closed Activities" />
</Titles>
</NavBarByRelationshipItem>

Here I have set the example of contact entity.