Question

So I have these partial classes. See below for the partial implementation of ParseFCIE and my question.

class CiscoSwitch
{
    Dictionary<int, CiscoVSAN> VSANList = new Dictionary<int, CiscoVSAN>();
    public void ParseFCIE(string block) 
    {}
}

class CiscoVSAN
{
     Dictionary<string, CiscoSwitch> MemberSwitches = new Dictionary<string, CiscoSwitch> ();
} 

Part of ParseFCIE is to check whether an incoming switch in the input data is already in the SwitchMembers dictionary of any CiscoVSAN objects, if not, add it. I have 2 dictionary statements. The first statement works, the second the compiler says it can’t determine the type of the predicate and I don’t know why. I prefer the second second statement since it is only one step. The first way I have search for the switch then check for a null value on the result of the search.

ParseFCIE(string block)
{  
     string DID = string.Empty;
     //partial implementation
     // 'this' is a CiscoSwitch object
     //this works
     var vsans= this.VSANList.SelectMany(v => v.Value.MemberSwitches.
                          Where(d => d.Value.switchName == this.switchName)); 
     // assume DID now has a value;
     // this line the compiler says the type arguments cannot be inferred from usage
     if (this.VSANList.SelectMany(v => v.Value.MemberSwitches.ContainsKey(DID))) 
     {}
}

Answer 1

if (this.VSANList.SelectMany(v => v.Value.MemberSwitches).Any(x => x.ContainsKey(DID))) {
}