ERROR in creating a random number

Question

I'm facing this problem : Argument 1: cannot convert from "long" to "int"   Random startGenerate = new Random (); //Create a number between 1000000000000000000 and 9223372036854775807 Int64 value = startGenerate.Next(1000000000000000000, 9223372036854775807);   I don't understand this error, anyone can help? Thanks,

Priyaranjan K S · Accepted Answer

Hi,   Try it this way :   private void button1_Click(object sender, EventArgs e) { long r = LongRandom(1000000000000000000, 9223372036854775807 , new Random()); MessageBox.Show(r.ToString()); }   long LongRandom(long min, long max, Random rand) { byte[] buf = new byte[8]; rand.NextBytes(buf); long longRand = BitConverter.ToInt64(buf, 0); return (Math.Abs(longRand % (max - min)) + min); }   Thanks, Priyan   If you found this useful Please mark this as Answer

Quang Dinh Luong · Answer

Thanks all for helping me! :)

Sujeet Suman · Answer

Quang let first clear the range of long or Int64.   Int64 Range:  From->  - 9,223,372,036,854,775,808   To->   9,223,372,036,854,775,807    So how you are getting error?    You can checkout from below link: https://msdn.microsoft.com/en-us/library/system.int64(v=vs.110).aspx     Are you doing something else?

Mukesh Kumar · Answer

Hi,   This is because of you are passing the number of digit in int64, which cross its limit.   thanks

Quang Dinh Luong · Answer

I still get this error Thanks!

Priyaranjan K S · Answer

Hi,   The reason is because inherently the function Random can have only Int32 as the arguments.Currently you are passing 64 bit values as parameter . That is why it is throwing the error .
Random(Int32) Initializes a new instance of the Random class, using the specified seed value.   You may use this implementation to work around this : long LongRandom ( long min , long max , Random rand ) { byte [] buf = new byte [ 8 ]; rand . NextBytes ( buf ); long longRand = BitConverter . ToInt64 ( buf , 0 ); return ( Math . Abs ( longRand % ( max - min )) + min ); } long r = LongRandom ( 1000000000000000000 , 9223372036854775807 , new Random ()); Console . WriteLine ( r ); Output : 8775056942043877407   Thanks, Priyan   If you found this useful Please mark this as Answer