Initialize a byte array to a certain value, other than the default null? [duplicate]

For small arrays use array initialisation syntax:

var sevenItems = new byte[] { 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20 };

For larger arrays use a standard for loop. This is the most readable and efficient way to do it:

var sevenThousandItems = new byte[7000];for (int i = 0; i < sevenThousandItems.Length; i++){    sevenThousandItems[i] = 0x20;}

Of course, if you need to do this a lot then you could create a helper method to help keep your code concise:

byte[] sevenItems = CreateSpecialByteArray(7);byte[] sevenThousandItems = CreateSpecialByteArray(7000);// ...public static byte[] CreateSpecialByteArray(int length){    var arr = new byte[length];    for (int i = 0; i < arr.Length; i++)    {        arr[i] = 0x20;    }    return arr;}

Use this to create the array in the first place:

byte[] array = Enumerable.Repeat((byte)0x20, <number of elements>).ToArray();

Replace <number of elements> with the desired array size.

You can use Enumerable.Repeat()

Enumerable.Repeat generates a sequence that contains one repeated value.

Array of 100 items initialized to 0x20:

byte[] arr1 = Enumerable.Repeat((byte)0x20,100).ToArray();