The check-and-set methods provide a mechanism for updating information only if the client knows the check (CAS) value. This can be used to prevent clients from updating values in the database that may have changed since the client obtained the value. Methods for storing and updating information support a CAS method that allows you to ensure that the client is updating the version of the data that the client retrieved.

The check value is in the form of a 64-bit integer which is updated every time the value is modified, even if the update of the value does not modify the binary data. Attempting to set or update a key/value pair where the CAS value does not match the value stored on the server will fail.

Store a value and get a CasResult with the Cas for that key.

var casResult = client.Cas(StoreMode.Set, "somekey", "somevalue");
logger.Debug("Cas value: " + casResult.Cas);

Cas() may also be used with a CAS value. With this overload, the return value is a CasResult, where success is determined by examining the CasResult's Result property.

var casv = client.GetWithCas("somekey");
var casResult = client.Cas(StoreMode.Set, "somekey", "somevalue", casv.Cas);
if (casResult.Result) {
	logger.Debug("Cas result was successful");
}

Perform a check and set operation, setting a TimeStamp expiration on the key.

var casv = client.GetWithCas("somekey");
var casResult = client.Cas(StoreMode.Set, "somekey", "somevalue", TimeSpan.FromMinutes(30), casv.Cas);
if (casResult.Result) {
	logger.Debug("Cas result was successful");
}

Perform a check and set operation, setting a DateTime expiration on the key.

var casv = client.GetWithCas("somekey");
var casResult = client.Cas(StoreMode.Set, "somekey", "somevalue", DateTime.Now.AddMinutes(30), casv.Cas);
if (casResult.Result) {
	logger.Debug("Cas result was successful");
}

Store a value and get an IStoreOperationResult return value.

var storeResult = client.ExecuteCas(StoreMode.Set, "somekey", "somevalue");
logger.Debug("Cas value: " + storeResult.Cas);

ExecuteCas() works like Cas() and may also be used with a CAS value. With this overload, the return value is an instance of an IStoreOperationResult.

var getResult = client.ExecutGet("somekey");
var storeResult = client.Cas(StoreMode.Set, "somekey", "somevalue", getResult.Cas);
if (storeResult.Result) {
	logger.Debug("Cas operation was successful");
}

Perform a check and set operation, setting a TimeStamp expiration on the key. Return an instance of an IStoreOperationResult.

var getResult = client.ExecutGet("somekey");
var storeResult = client.Cas(StoreMode.Set, "somekey", "somevalue", TimeSpan.FromMinutes(30), getResult.Cas);
if (storeResult.Result) {
	logger.Debug("Cas operation was successful");
}

Perform a check and set operation, setting a DateTime expiration on the key. Return an instance of an IStoreOperationResult.

var getResult = client.ExecutGet("somekey");
var storeResult = client.Cas(StoreMode.Set, "somekey", "somevalue", DateTime.Now.AddMinutes(30), getResult.Cas);
if (storeResult.Result) {
	logger.Debug("Cas operation was successful");
}