Using the QueryExpression Class

[C#]
// Set up the CRM Service.
CrmAuthenticationToken token = new CrmAuthenticationToken();
token.AuthenticationType = 0; 
token.OrganizationName = "AdventureWorksCycle";
 
CrmService service = new CrmService();
service.Url = ""http://<servername>:<port>/mscrmservices/2007/crmservice.asmx";
service.CrmAuthenticationTokenValue = token;
service.Credentials = System.Net.CredentialCache.DefaultCredentials;

// Create a column set holding the names of the columns to be retrieved.
ColumnSet cols = new ColumnSet();
cols.Attributes = new string [] {"name", "accountid"};

// Create the ConditionExpression.
ConditionExpression condition = new ConditionExpression();

// Set the condition to be when the account owner's last name is not Cannon.
condition.AttributeName = "lastname";
condition.Operator = ConditionOperator.Equal;
condition.Values = new string [] {"Cannon"};

// Build the filter that is based on the condition.
FilterExpression filter = new FilterExpression();
filter.FilterOperator = LogicalOperator.And;
filter.Conditions = new ConditionExpression[] {condition};

// Create a LinkEntity to link the owner's information to the account.
LinkEntity link = new LinkEntity();

// Set the LinkEntity properties.
link.LinkCriteria = filter;

// Set the linking entity to account.
link.LinkFromEntityName = EntityName.account.ToString();

// Set the linking attribute to owninguser.
link.LinkFromAttributeName = "owninguser";

// The attribute being linked to is systemuserid.
link.LinkToAttributeName = "systemuserid";

// The entity being linked to is systemuser.
link.LinkToEntityName = EntityName.systemuser.ToString();

// Create an instance of the query expression class.
QueryExpression query = new QueryExpression();

// Set the query properties.
query.EntityName = EntityName.account.ToString();
query.ColumnSet = cols;
query.LinkEntities = new LinkEntity[] {link};

// Create the request.
RetrieveMultipleRequest retrieve = new RetrieveMultipleRequest();

// Set the request properties.
retrieve.Query = query;

// Execute the request.
RetrieveMultipleResponse retrieved2 = (RetrieveMultipleResponse) service.Execute(retrieve);

[Visual Basic .NET]
' Set up the CRM Service.
Dim token As New CrmAuthenticationToken()
token.AuthenticationType = 0
token.OrganizationName = "AdventureWorksCycle";
 
Dim service As New CrmService()
service.Url = ""http://<servername>:<port>/mscrmservices/2007/crmservice.asmx";
service.CrmAuthenticationTokenValue = token;
service.Credentials = System.Net.CredentialCache.DefaultCredentials

' Create a column set holding the names of the columns to be retrieved.
Dim cols As New ColumnSet()
cols.Attributes = New String() {"name", "accountid"}

' Create the ConditionExpression.
Dim condition As New ConditionExpression()

' Set the condition to be when the account owner's last name is not Cannon.
condition.AttributeName = "lastname"
condition.[Operator] = ConditionOperator.NotEqual
condition.Values = New String() {"Cannon"}

' Build the filter that is based on the condition.
Dim filter As New FilterExpression()
filter.FilterOperator = LogicalOperator.And
filter.Conditions = New ConditionExpression() {condition}

' Create a LinkEntity to link the owner's information to the account.
Dim link As New LinkEntity()

' Set the LinkEntity properties.
link.LinkCriteria = filter

' Set the linking entity to account.
link.LinkFromEntityName = EntityName.account.ToString()

' Set the linking attribute to owninguser.
link.LinkFromAttributeName = "owninguser"

' The attribute being linked to is systemuserid.
link.LinkToAttributeName = "systemuserid"

' The entity being linked to is systemuser.
link.LinkToEntityName = EntityName.systemuser.ToString()

' Create the query expression.
Dim query As New QueryExpression()

' Set the query properties.
query.EntityName = EntityName.account.ToString()
query.ColumnSet = cols
query.LinkEntities = New LinkEntity() {link}

' Create the request.
Dim retrieve As New RetrieveMultipleRequest()

' Set the request properties.
retrieve.Query = query

' Execute the request. 
Dim retrieved2 As RetrieveMultipleResponse = CType(service.Execute(retrieve), RetrieveMultipleResponse)