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Conditional update

Atomically sets the value to the given updated value if the current value == the expected value.

// *******************************************
// synchronous methods
// *******************************************

// Backendless.Counters approach
public bool Backendless.Counters.CompareAndSet( String counterName, Int64 expected, Int64 updated );

// IAtomic approach
IAtomic<T> counter = Backendless.Counters.Of<T>( String counterName );
public bool counter.CompareAndSet( Int64 expected, Int64 updated );

// *******************************************
// asynchronous methods
// *******************************************

// Backendless.Counters approach
public void Backendless.Counters.CompareAndSet<T>( String counterName, Int64 expected, Int64 updated, AsyncCallback<bool> callback );

// IAtomic approach
IAtomic<T> counter = Backendless.Counters.Of<T>( String counterName );
public void counter.CompareAndSet( Int64 expected, Int64 updated, AsyncCallback<T> callback );

where:

Argument                Description
counterName name of the counter to update.
expected the expected value of the counter. If the current value equals the expected value, the counter is set to the "updated" value.
updated the new value to assign to the counter if the current value equals the expected value.
callback the callback used for asynchronous calls to indicate that the operation has either successfully completed or resulted in error.

Example

AsyncCallback<bool> callback = new AsyncCallback<bool>(
  result =>
  {
    System.Console.WriteLine( "[ASYNC] valud has been updated? - " + result );
  },
  fault =>
  {
     System.Console.WriteLine( "Error - " + fault );
  } );

Backendless.Counters.CompareAndSet( "my counter", 1000, 2000, callback );

IAtomic<int> myCounter = Backendless.Counters.Of<int>( "my counter" );
bool updateResult = myCounter.CompareAndSet( 1000, 2000 );
System.Console.WriteLine( "[SYNC] value has been updated? - " + updateResult );

updateResult = Backendless.Counters.CompareAndSet( "my counter", 2000, 3000 );
System.Console.WriteLine( "[SYNC] value has been updated? - " + updateResult );