# getInt64 method

int getInt64 (int byteOffset, [ Endian endian = Endian.big ])

Returns the (possibly negative) integer represented by the eight bytes at the specified `byteOffset` in this object, in two's complement binary form.

The return value will be between -263 and 263 - 1, inclusive.

Throws RangeError if `byteOffset` is negative, or `byteOffset + 8` is greater than the length of this object.

## Implementation

    int getInt64(int byteOffset, [Endian endian = Endian.big]);