Packageflash.utils
Interfacepublic interface IDataOutput
Implementors ByteArray, FileStream, Socket

The IDataOutput interface provides a set of methods for writing binary data. This interface is the I/O counterpart to the IDataInput interface, which reads binary data. The IDataOutput interface is implemented by the FileStream, Socket and ByteArray classes.

All IDataInput and IDataOutput operations are "bigEndian" by default (the most significant byte in the sequence is stored at the lowest or first storage address), and are nonblocking.

Sign extension matters only when you read data, not when you write it. Therefore, you do not need separate write methods to work with IDataInput.readUnsignedByte() and IDataInput.readUnsignedShort(). In other words:

View the examples

See also

IDataInput interface
endian
FileStream class
Socket class
URLStream class
ByteArray class

Public Properties
 PropertyDefined By
  endian : String
The byte order for the data, either the BIG_ENDIAN or LITTLE_ENDIAN constant from the Endian class.
IDataOutput
  objectEncoding : uint
Used to determine whether the AMF3 or AMF0 format is used when writing or reading binary data using the writeObject() method.
IDataOutput
Public Methods
 MethodDefined By
  
writeBoolean(value:Boolean):void
Writes a Boolean value.
IDataOutput
  
writeByte(value:int):void
Writes a byte.
IDataOutput
  
writeBytes(bytes:ByteArray, offset:uint = 0, length:uint = 0):void
Writes a sequence of bytes from the specified byte array, bytes, starting at the byte specified by offset (using a zero-based index) with a length specified by length, into the file stream, byte stream, or byte array.
IDataOutput
  
writeDouble(value:Number):void
Writes an IEEE 754 double-precision (64-bit) floating point number.
IDataOutput
  
writeFloat(value:Number):void
Writes an IEEE 754 single-precision (32-bit) floating point number.
IDataOutput
  
writeInt(value:int):void
Writes a 32-bit signed integer.
IDataOutput
  
writeMultiByte(value:String, charSet:String):void
Writes a multibyte string to the file stream, byte stream, or byte array, using the specified character set.
IDataOutput
  
writeObject(object:*):void
Writes an object to the file stream, byte stream, or byte array, in AMF serialized format.
IDataOutput
  
writeShort(value:int):void
Writes a 16-bit integer.
IDataOutput
  
writeUnsignedInt(value:uint):void
Writes a 32-bit unsigned integer.
IDataOutput
  
writeUTF(value:String):void
Writes a UTF-8 string to the file stream, byte stream, or byte array.
IDataOutput
  
writeUTFBytes(value:String):void
Writes a UTF-8 string.
IDataOutput
Property Detail
endianproperty
endian:String

The byte order for the data, either the BIG_ENDIAN or LITTLE_ENDIAN constant from the Endian class.



Implementation
    public function get endian():String
    public function set endian(value:String):void

See also

Endian class
objectEncodingproperty 
objectEncoding:uint

Used to determine whether the AMF3 or AMF0 format is used when writing or reading binary data using the writeObject() method. The value is a constant from the ObjectEncoding class.



Implementation
    public function get objectEncoding():uint
    public function set objectEncoding(value:uint):void

See also

IDataInput.readObject()
writeObject()
ObjectEncoding class
Method Detail
writeBoolean()method
public function writeBoolean(value:Boolean):void

Writes a Boolean value. A single byte is written according to the value parameter, either 1 if true or 0 if false.

Parameters

value:Boolean — A Boolean value determining which byte is written. If the parameter is true, 1 is written; if false, 0 is written.

writeByte()method 
public function writeByte(value:int):void

Writes a byte. The low 8 bits of the parameter are used; the high 24 bits are ignored.

Parameters

value:int — A byte value as an integer.

writeBytes()method 
public function writeBytes(bytes:ByteArray, offset:uint = 0, length:uint = 0):void

Writes a sequence of bytes from the specified byte array, bytes, starting at the byte specified by offset (using a zero-based index) with a length specified by length, into the file stream, byte stream, or byte array.

If the length parameter is omitted, the default length of 0 is used and the entire buffer starting at offset is written. If the offset parameter is also omitted, the entire buffer is written.

If the offset or length parameter is out of range, they are clamped to the beginning and end of the bytes array.

Parameters

bytes:ByteArray — The byte array to write.
 
offset:uint (default = 0) — A zero-based index specifying the position into the array to begin writing.
 
length:uint (default = 0) — An unsigned integer specifying how far into the buffer to write.

writeDouble()method 
public function writeDouble(value:Number):void

Writes an IEEE 754 double-precision (64-bit) floating point number.

Parameters

value:Number — A double-precision (64-bit) floating point number.

writeFloat()method 
public function writeFloat(value:Number):void

Writes an IEEE 754 single-precision (32-bit) floating point number.

Parameters

value:Number — A single-precision (32-bit) floating point number.

writeInt()method 
public function writeInt(value:int):void

Writes a 32-bit signed integer.

Parameters

value:int — A byte value as a signed integer.

writeMultiByte()method 
public function writeMultiByte(value:String, charSet:String):void

Writes a multibyte string to the file stream, byte stream, or byte array, using the specified character set.

Parameters

value:String — The string value to be written.
 
charSet:String — The string denoting the character set to use. Possible character set strings include "shift-jis", "cn-gb", "iso-8859-1", and others. For a complete list, see Supported Character Sets.

writeObject()method 
public function writeObject(object:*):void

Writes an object to the file stream, byte stream, or byte array, in AMF serialized format.

Parameters

object:* — The object to be serialized.

See also

objectEncoding
flash.net.registerClassAlias()
writeShort()method 
public function writeShort(value:int):void

Writes a 16-bit integer. The low 16 bits of the parameter are used; the high 16 bits are ignored.

Parameters

value:int — A byte value as an integer.

writeUnsignedInt()method 
public function writeUnsignedInt(value:uint):void

Writes a 32-bit unsigned integer.

Parameters

value:uint — A byte value as an unsigned integer.

writeUTF()method 
public function writeUTF(value:String):void

Writes a UTF-8 string to the file stream, byte stream, or byte array. The length of the UTF-8 string in bytes is written first, as a 16-bit integer, followed by the bytes representing the characters of the string.

Parameters

value:String — The string value to be written.


Throws
RangeError — If the length is larger than 65535.
writeUTFBytes()method 
public function writeUTFBytes(value:String):void

Writes a UTF-8 string. Similar to writeUTF(), but does not prefix the string with a 16-bit length word.

Parameters

value:String — The string value to be written.

Examples How to use this example
DataOutputExample.as

The following example uses the class DataOutputExample to write a boolean and the double-precision floating-point representation of pi to a byte array. This is accomplished using the following steps:
  1. Declare a new ByteArray object instance byteArr.
  2. Write the byte-equivalent value of the Boolean false and the double-precision floating-point equivalent of the mathematical value of pi.
  3. Read back the boolean and double-precision floating-point number.

Notice how a code segment is added at the end to check for end of file errors to ensure that the byte stream is not read past its end.

package {
    import flash.display.Sprite;
    import flash.utils.ByteArray;
    import flash.errors.EOFError;

    public class DataOutputExample extends Sprite {        
        public function DataOutputExample() {
            var byteArr:ByteArray = new ByteArray();

            byteArr.writeBoolean(false);
            byteArr.writeDouble(Math.PI);
            
            byteArr.position = 0;

            try {
                trace(byteArr.readBoolean()); // false
            } 
            catch(e:EOFError) {
                trace(e);           // EOFError: Error #2030: End of file was encountered.
            }
                        
            try {
                trace(byteArr.readDouble());    // 3.141592653589793
            } 
            catch(e:EOFError) {
                trace(e);           // EOFError: Error #2030: End of file was encountered.
            }
            
            try {
                trace(byteArr.readDouble());
            } 
            catch(e:EOFError) {
                trace(e);        // EOFError: Error #2030: End of file was encountered.
            }
        }
    }
}



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Thu Aug 13 2009, 03:11 AM -07:00