java hashtable to c# dictionary

问题

Java code:

//BleDevice is a class
public Hashtable<String, BleDevice> meusBLEs = new Hashtable<String, BleDevice>();

//BleRequest is another class
BleRequest currentRequest = null;

//deviceAddress is a string from BleRequest
BleDevice ble=meusBLEs.get(currentRequest.deviceAddress);

I'm using a hashtable and set the value to the BleDevice variable;

Now what I'm trying to do in c#, is the same thing but using Dictionary:

public Dictionary<String, BleDevice> meusBLEs = new Dictionary<String, BleDevice>();

BleRequest currentRequest = null;

BleDevice ble = meusBLEs.get...//HERE'S IS WHAT I DON`T KNOW HOW TO DO. THE METHOD GET DON`T EXIST

I can't use hashtable in c# cause I can't set the parameter like java's hashtable.

回答1:

BleDevice ble = meusBLEs[currentRequest.deviceAddress];

回答2:

The behavior is a bit different in .NET than Java; in particular, while the Java's get() method may return null for missing values, such a convention is not applicable in .NET where the value type may not be a reference type.

There are actually two standard ways to retrieve a value:

BleDevice ble = meusBLEs[currentRequest.deviceAddress];

The statement above will throw an exception if the value for key currentRequest.deviceAddress is not present in the dictionary. Alternatively, you can use the TryGetValue method:

BleDevice ble;
/* bool found = */ meusBLEs.TryGetValue(currentRequest.deviceAddress, out ble);

If TryGetValue returns false, the value of the out parameter will be default(TValue).

回答3:

Just do this: BleDevice ble = meusBLEs[the_key_you_have].

来源：https://stackoverflow.com/questions/26061406/java-hashtable-to-c-sharp-dictionary