Convert.ToInt64 Method (Byte)

Converts the value of the specified 8-bit unsigned integer to the equivalent 64-bit signed integer.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public static long ToInt64(
	byte value


Type: System.Byte
An 8-bit unsigned integer.

Return Value

Type: System.Int64
The 64-bit signed integer equivalent to the value of value.

The following code sample illustrates the conversion of a Byte value to an Int64, using ToInt64.

public void ConvertLongByte(long longVal)
   byte byteVal = 0;

   // A conversion from Long to byte can overflow.
      byteVal = System.Convert.ToByte(longVal);
      outputBlock.Text += String.Format("{0} as a byte is {1}",
         longVal, byteVal) + "\n";
   catch (System.OverflowException)
      outputBlock.Text += String.Format(
         "Overflow in long-to-byte conversion.") + "\n";

   // A conversion from Byte to long cannot overflow.
   longVal = System.Convert.ToInt64(byteVal);
   outputBlock.Text += String.Format("{0} as an Int64 is {1}",
      byteVal, longVal) + "\n";


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.