A fixed-length, random-access sequence of bytes that also provides random and unaligned access to the fixed-width integers and floating point numbers represented by those bytes.
ByteData may be used to pack and unpack data from external sources
(such as networks or files systems), and to process large quantities
of numerical data more efficiently than would be possible
with ordinary List implementations.
ByteData can save space, by eliminating the need for object headers,
and time, by eliminating the need for data copies.
Finally, ByteData may be used to intentionally reinterpret the bytes
representing one arithmetic type as another.
For example this code fragment determine what 32-bit signed integer
is represented by the bytes of a 32-bit floating point number:
var buffer = new Uint8List(8).buffer;
var bdata = new ByteData.view(buffer);
bdata.setFloat32(0, 3.04);
int huh = bdata.getInt32(0);
- Implements
Constructors
- ByteData(int length)
-
Creates a ByteData of the specified length (in elements), all of whose bytes are initially zero.
factory - ByteData.view(ByteBuffer buffer, [int offsetInBytes = 0, int length])
-
Creates an ByteData view of the specified region in
buffer.…factory
Properties
- buffer → ByteBuffer
-
Returns the byte buffer associated with this object.
read-only, inherited - elementSizeInBytes → int
-
Returns the number of bytes in the representation of each element in this list.
read-only, inherited - hashCode → int
-
Get a hash code for this object.…
read-only, inherited - lengthInBytes → int
-
Returns the length of this view, in bytes.
read-only, inherited - offsetInBytes → int
-
Returns the offset in bytes into the underlying byte buffer of this view.
read-only, inherited - runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
Operators
-
operator ==(
other) → bool -
The equality operator.…
inherited
Methods
-
getFloat32(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → double -
Returns the floating point number represented by the four bytes at the specified
byteOffsetin this object, in IEEE 754 single-precision binary floating-point format (binary32).… -
getFloat64(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → double -
Returns the floating point number represented by the eight bytes at the specified
byteOffsetin this object, in IEEE 754 double-precision binary floating-point format (binary64).… -
getInt8(
int byteOffset) → int -
Returns the (possibly negative) integer represented by the byte at the specified
byteOffsetin this object, in two's complement binary representation.… -
getInt16(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the (possibly negative) integer represented by the two bytes at the specified
byteOffsetin this object, in two's complement binary form.… -
getInt32(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the (possibly negative) integer represented by the four bytes at the specified
byteOffsetin this object, in two's complement binary form.… -
getInt64(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the (possibly negative) integer represented by the eight bytes at the specified
byteOffsetin this object, in two's complement binary form.… -
getUint8(
int byteOffset) → int -
Returns the positive integer represented by the byte at the specified
byteOffsetin this object, in unsigned binary form.… -
getUint16(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the positive integer represented by the two bytes starting at the specified
byteOffsetin this object, in unsigned binary form.… -
getUint32(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the positive integer represented by the four bytes starting at the specified
byteOffsetin this object, in unsigned binary form.… -
getUint64(
int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN]) → int -
Returns the positive integer represented by the eight bytes starting at the specified
byteOffsetin this object, in unsigned binary form.… -
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.…
inherited -
setFloat32(
int byteOffset, double value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the four bytes starting at the specified
byteOffsetin this object to the IEEE 754 single-precision binary floating-point (binary32) representation of the specifiedvalue.… -
setFloat64(
int byteOffset, double value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the eight bytes starting at the specified
byteOffsetin this object to the IEEE 754 double-precision binary floating-point (binary64) representation of the specifiedvalue.… -
setInt8(
int byteOffset, int value) → void -
Sets the byte at the specified
byteOffsetin this object to the two's complement binary representation of the specifiedvalue, which must fit in a single byte.… -
setInt16(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the two bytes starting at the specified
byteOffsetin this object to the two's complement binary representation of the specifiedvalue, which must fit in two bytes.… -
setInt32(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the four bytes starting at the specified
byteOffsetin this object to the two's complement binary representation of the specifiedvalue, which must fit in four bytes.… -
setInt64(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the eight bytes starting at the specified
byteOffsetin this object to the two's complement binary representation of the specifiedvalue, which must fit in eight bytes.… -
setUint8(
int byteOffset, int value) → void -
Sets the byte at the specified
byteOffsetin this object to the unsigned binary representation of the specifiedvalue, which must fit in a single byte.… -
setUint16(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the two bytes starting at the specified
byteOffsetin this object to the unsigned binary representation of the specifiedvalue, which must fit in two bytes.… -
setUint32(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the four bytes starting at the specified
byteOffsetin this object to the unsigned binary representation of the specifiedvalue, which must fit in four bytes.… -
setUint64(
int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]) → void -
Sets the eight bytes starting at the specified
byteOffsetin this object to the unsigned binary representation of the specifiedvalue, which must fit in eight bytes.… -
toString(
) → String -
Returns a string representation of this object.
inherited