Android : Convert Long to Byte [] in android by same result in c#

I want to convert a long value to a byte array in my android app. my app must convert this value to byte[] by same result when i convert it in C# ! but in android i got (-) number for large number ! I search in net for this problem and found many ways to Only convert long to byte[] but never found anything about this problem

Long value : 47063350

C# value:

    [0] 0   byte
    [1] 0   byte
    [2] 0   byte
    [3] 0   byte
    [4] 2   byte
    [5] 206 byte
    [6] 33  byte
    [7] 54  byte

Android value :

[0] = 0
[1] = 0
[2] = 0
[3] = 0
[4] = 2
[5] = -50
[6] = 33
[7] = 54

206 now is -50 !!!

Excuse my if my English is bad