How do I convert an NSNumber to NSData?
I would not recommend NSKeyedArchiver
for such a simple task, because it adds PLIST overhead on top of it and class versioning.
Pack:
NSUInteger index = <some number>;NSData *payload = [NSData dataWithBytes:&index length:sizeof(index)];
Send:
[session sendDataToAllPeers:payload withDataMode:GKSendDataReliable error:nil];
Unpack (in the GKSession receive handler):
NSUInteger index;[payload getBytes:&index length:sizeof(index)];
Swift
var i = 123let data = NSData(bytes: &i, length: sizeof(i.dynamicType))var i2 = 0data.getBytes(&i2, length: sizeof(i2.dynamicType))print(i2) // "123"
To store it:
NSData *numberAsData = [NSKeyedArchiver archivedDataWithRootObject:indexNum];
To convert it back to NSNumber:
NSNumber *indexNum = [NSKeyedUnarchiver unarchiveObjectWithData:numberAsData];
Why not send the integer directly like this:
NSData * indexData = [NSData dataWithBytes:&index length:sizeof(index)];[gkSession sendDataToAllPeers:indexData withDataMode:GKSendDataReliable error:nil];