Exceptions Exception TypeCondition ArgumentException The sum of offset and count is greater than the buffer length. IOException An I/O error occurs, such as the file being closed. NotSupportedException The stream does not support writing, or the stream is already closed.
ObjectDisposedException Methods were called after the stream was closed.Remarks Use the Stream.CanWrite property to determine whether the current instance supports writing. If the write operation is successful, the position within the stream advances by the number of bytes written. If an exception occurs, the position within the stream remains unchanged. Given a file, now our task is to read and write byte array to a file with the help of FileStream Class Filestream class in C# is the part of System.IO namespace and System.Runtime.dll assembly. This class offers a stream for a file that supports synchronous and asynchronous read and write operations. This class can be used to read from, write to, open, and close files on a file system.
The input and output buffers and that is why it gives better performance. This class provides different types of methods and the read and write method is one of them. It is easy to convert between streams, byte arrays, and buffers.
The methods to copy a stream into a byte array or send a byte array into a stream already exist as part of the .NET Framework. The WindowsRuntimeBufferExtensions class provides additional facilities for converting between buffers and byte arrays. It exists in the System.Runtime.InteropServices.WindowsRuntime namespace.
It provides several methods including AsBuffer (cast a Byte[] instance to an IBuffer), AsStream and ToArray (cast an IBuffer instance to a Byte[] instance). The FileStream's Read method reads a block of bytes from the stream and writes the data in a given buffer. The first argument is the byte offset in array at which the read bytes will be placed. The Encoding.UTF8.GetStringdecodes all the bytes in the specified byte array into a string.
Protocol buffers are the flexible, efficient, automated solution to solve exactly this problem. With protocol buffers, you write a .proto description of the data structure you wish to store. From that, the protocol buffer compiler creates a class that implements automatic encoding and parsing of the protocol buffer data with an efficient binary format. The generated class provides getters and setters for the fields that make up a protocol buffer and takes care of the details of reading and writing the protocol buffer as a unit. Importantly, the protocol buffer format supports the idea of extending the format over time in such a way that the code can still read data encoded with the old format. This constructor is called by derived class constructors to initialize state in this type.
ArgumentExceptionoffset subtracted from the buffer length is less than count. ArgumentOutOfRangeExceptionoffset or count are negative. ObjectDisposedException The current stream instance is closed.Remarks This method overrides Stream.Write. The offset parameter gives the offset of the first byte in buffer to write from, and the count parameter gives the number of bytes to write. If the write operation is successful, the current position within the stream is advanced by the number of bytes written.
If an exception occurs, the current position within the stream is unchanged. If the specified value is less than the current length of the stream, the stream is truncated. If the specified value is larger than the current capacity and the stream is resizable, the capacity is increased, and the current position within the stream is unchanged.
If the length is increased, the contents of the stream between the old and the new length are initialized to zeros. Implementations of this method read a maximum of count bytes from the current stream and store them in buffer beginning at offset. The current position within the stream is advanced by the number of bytes read; however, if an exception occurs, the current position within the stream remains unchanged. The return value is zero only if the position is currently at the end of the stream. The implementation will block until at least one byte of data can be read, in the event that no data is available.Read returns 0 only when there is no more data in the stream and no more is expected .
An implementation is free to return fewer bytes than requested even if the end of the stream has not been reached. When this method returns, the buffer contains the specified byte array with the values between offset and (offset + count) replaced by the bytes read from the current source. Memory streams created with an unsigned byte array provide a non-resizable stream view of the data, and can only be written to. When using a byte array, you can neither append to nor shrink the stream, although you might be able to modify the existing contents depending on the parameters passed into the constructor.
Empty memory streams are resizable, and can be written to and read from. Recently I was looking for a sample code that could convert byte array[] to an image in C# ASP.Net. It's very useful when you are writing an ASP.Net Web API method to upload an image or a file on the server. Net convert bytearray to image c# , vb.net byte arrays can be easily ...
Has a save function which allows developers to save an image to a file in any image ... I was working on some Stream extensions today and added a method which will read all of the data from a stream in to a byte array. Some of the classes which derive from Stream provide a similar method (MemoryStream, for example, provides a GetBuffer() method to do this). The drawback here is that the base Stream class doesn't provide an abstract GetBuffer() method; instead it's up to each individual derived class to implement such a method. This is perfectly reasonable as a stream may not have an underlying buffer for storage like MemoryStream does.
Stream is an abstract class, it can not initialize an object by itself, you can initialize a Stream object from the Constructors of the subclass. Stream class provides the basic methods of working with data streams, namely the method of read/write a byte or an array of bytes. The traditional method for reading data from a file, website, or other source in .NET is to use a stream. A stream allows you to transfer data into a data structure that you can read and manipulate.
Streams may also provide the ability to transfer the contents of a data structure back to the stream to write it. Some streams support seeking, or finding a position within a stream the same way you might skip ahead to a different scene on a DVD movie. Exceptions Exception TypeCondition IOException The stream is closed. A stream is an abstraction of a sequence of bytes, such as a file, an input/output device, an inter-process communication pipe, or a TCP/IP socket. FileStream provides a Stream for a file, supporting both synchronous and asynchronous read and write operations. A stream is a flow of data from a source into a destination.
The source or destination can be a disk, memory, socket, or other programs. Stream is the abstract base class of all streams and it Provides a generic view of a sequence of bytes. The Streams Object involve three fundamental operations such as Reading, Writing and Seeking.
In some situations we may need to convert these stream to byte array. This lesson explain how to convert a stream to byteArray. That's why other classes are used to work with text files. When this method returns, contains the specified byte array with the values between offset and(offset + count - 1) replaced by the characters read from the current stream. Here, arr is a byte array, loc is the 0-based byte offset in arr at which the copying of bytes starts to the stream, and the count is the total bytes read/write to or from a file.
When this method returns, contains the specified byte array with the values between offset and (offset + count – 1) replaced by the bytes read from the current source. If a stream supports the Length property, a byte array can be directly created. The advantage is that MemoryStream.ToArray creates the array twice. If the stream does not support the Length property, it will throw NotSupportedException exception. I had my suspicions, but as always, the best way to optimize code is to measure it. I set up a simple test application which went through a four minute MP3 file, converting it to WAV and finding the peak sample values over periods of a few hundred milliseconds at a time.
This is the type of code you would use for waveform drawing. I measured how long each one took to go through a whole file . I was careful to write code that avoided creating work for the garbage collector.
This .Net C# code snippet save byte array in to an external file. At this point, you might be asking "Why unnecessary overhead? " This question brings us to System.Buffer, which has been available in .NET since .NET 1.1 although you've probably never heard of it until now. A Buffer is designed to manipulate arrays of primitive types and treats each type as a series of bytes without any regard to behavior or limitations.
Remember, Stream.Read returns an array of bytes and byte is a primitive type. So we can use Buffer to copy the array elements directly in memory rather than by index, which provides better performance than Array.Copy. Taking that into consideration, you read streams the same way. The call to Stream.Read() takes an array of bytes as a buffer to fill during the read operation.
It would be nice to be able to get the entire contents of the stream as a byte array. I put out a situation, you create a BufferedStream wrap FileStream, for the purpose of writing data to the file. Using BufferedStream in this case reduces the number of times to write down the drive, and so it increases the efficiency of the program. The Stream.Read and Stream.Write methods read and write data in a variety of formats.
For streams that support seeking, use the Stream.Seek and Stream.SetLength methods and the Stream.Position and Stream.Length properties to query and modify the current position and length of a stream. The MemoryStream class is used to create a byte stream, which is used to write or read bytes to/from an internal array stored in the memory. The MemoryStream class is defined in the System.IO namespace.
Sure, buffer needs to be "big ebough" but proper design of an application should include transactions and delimiters. In this configuration each transaction would have a preset length thus your array would anticipate certain number of bytes and insert it into correctly sized buffer. Delimiters would ensure transaction integrity and would be supplied within each transaction. To make your application even better, you could use 2 channels . One would communicate fixed length control message transactions that would include information about size and sequence number of data transaction to be transferred using data channel.
Receiver would acknowledge buffer creation and only then data would be sent. If you have no control over stream sender than you need multidimensional array as a buffer. Component arrays would be small enough to be manageable and big enough to be practical based on your estimate of expected data.
Process logic would seek known start delimiters and then ending delimiter in subsequent element arrays. Once ending delimiter is found, new buffer would be created to store relevant data between delimiters and initial buffer would have to be restructured to allow data disposal. Here, arr is a byte array, loc is the byte offset in arr at which the read bytes will be put, and the count is the total bytes read/write to or from a file.
This post has shown you examples about converting bitmap to byte array c# and also convert video to byte array c#. Your article is very good, it demonstrates several advantages of Stream over byte arrays. For people reading this, I would also like to mention the situations where we are reading data from files or network and the advantages Stream provides over byte[] in these contexts. Yesterday I was working on a bit of code that had to read theXMPmeta data from a file. It is not located at a certain position, so I had to scan the file.
XMP, being plain XML, can be found by simple string matching. After some searching I've found many solutions that read the entire file into memory and perform a regular expression search or a string comparison. That'snotgoing to work for me, because I have files that are+100MB! So I wrote some code that searches for a string in a stream.
It is very useful in many scenarios because byte arrays can be easily compared, compressed, stored, or converted to other data types. When the buffer is full a new array with a larger size to be created, and copy the data from the old array. Stream IO The above image shows that FileStream reads bytes from a physical file, and then StreamReader reads strings by converting those bytes to strings. In the same way, the StreamWriter takes a string and converts it into bytes and writes to the FileStream, and then the FileStream writes the bytes to a physical file. So, the FileStream deals with bytes, where as StreamReader and StreamWriter deals with strings. The BufferedStream class provides the capability of wrapping a buffered stream around another stream in order to improve read and write performance.
The static File class in the System.IO namespace provides a simple static method WriteAllBytes() that we can use to write all the data from a byte array to a file. Our method simply creates a FileStream object passing in the intended file path as the only argument. Then, it uses the instance method called Write() to write the byte array into the created file. Reader & writer classes provides functionality to read bytes from Stream classes and converts bytes into appropriate encoding. Exceptions Exception TypeCondition IOException An I/O error occurs, such as the file being closed. NotSupportedException The stream does not support both writing and seeking, such as if the stream is constructed from a pipe or console output.
ObjectDisposedException Methods were called after the stream was closed.Remarks If the specified value is less than the current length of the stream, the stream is truncated. If the specified value is larger than the current length of the stream, the stream is expanded. If the stream is expanded, the contents of the stream between the old and the new length are not defined. A stream must support both writing and seeking for SetLength to work. The Read method will return zero only if the end of the stream is reached.
