将 null/nothing 设置为查找字段

Question

I need to set null/nothing to lookup field in crm 2011, using c# code. I'm using early bound entities.

My method has parameters: public Guid ZalozeniPodporSmluvy(String name, Guid programid)

When i try to pass Guid - programid = Guid.Empty to EntityReference of programid property, i get error:

Pgrlf_pojistna_smlouva With Id = 00000000-0000-0000-0000-000000000000 Does Not Exist

The same i get when i try directly assign null -

pgrlf_programid = new EntityReference("pgrlf_program", null)
{
    supported_contracts PodporSmlouva = new supported_contracts()
    {
        name = name,
        programid = new EntityReference("program", programid),
    };

    PodporSmlouva.Id = _proxy.Create(PodporSmlouva);

    var entity = _proxy.Retrieve("supported_contracts", PodporSmlouva.Id, new ColumnSet(true));

    return entity.Id;
}

Sometimes i need to pass exact guid to this method and make a reference between two entities and sometimes not. How can i pass nothing to programid and create no reference?

Answer 1

This will do the trick.

programid  = null;

If you want conditional do something like

if(condition staisfies){
programid  = null;
}else{
programid = new EntityReference("program", programid)
}