TextReader.ReadBlock Method

Definition

Namespace:

System.IO

Assembly:

System.Runtime.dll

Overloads

ReadBlock(Char[], Int32, Int32)	Reads a specified maximum number of characters from the current text reader and writes the data to a buffer, beginning at the specified index.
ReadBlock(Span<Char>)	Reads the characters from the current stream and writes the data to a buffer.

ReadBlock(Char[], Int32, Int32)

Source:

TextReader.cs

Reads a specified maximum number of characters from the current text reader and writes the data to a buffer, beginning at the specified index.

public:
 virtual int ReadBlock(cli::array <char> ^ buffer, int index, int count);

public virtual int ReadBlock (char[] buffer, int index, int count);

abstract member ReadBlock : char[] * int * int -> int
override this.ReadBlock : char[] * int * int -> int

Public Overridable Function ReadBlock (buffer As Char(), index As Integer, count As Integer) As Integer

Parameters

buffer

Char[]

When this method returns, this parameter contains the specified character array with the values between index and (index + count -1) replaced by the characters read from the current source.

index

Int32

The position in buffer at which to begin writing.

count

Int32

The maximum number of characters to read.

Returns

Int32

The number of characters that have been read. The number will be less than or equal to count, depending on whether all input characters have been read.

Exceptions

ArgumentNullException

buffer is null.

ArgumentException

The buffer length minus index is less than count.

ArgumentOutOfRangeException

index or count is negative.

ObjectDisposedException

The TextReader is closed.

IOException

An I/O error occurs.

Remarks

The position of the underlying text reader is advanced by the number of characters that were read into buffer.

The method blocks until either count characters are read, or all characters have been read. This is a blocking version of Read.

See also

• ReadBlock(Char[], Int32, Int32)
• File and Stream I/O
• How to: Read Text from a File
• How to: Write Text to a File

ReadBlock(Span<Char>)

Source:

TextReader.cs

Reads the characters from the current stream and writes the data to a buffer.

public:
 virtual int ReadBlock(Span<char> buffer);

public virtual int ReadBlock (Span<char> buffer);

abstract member ReadBlock : Span<char> -> int
override this.ReadBlock : Span<char> -> int

Public Overridable Function ReadBlock (buffer As Span(Of Char)) As Integer

Parameters

buffer

Span<Char>

When this method returns, contains the specified span of characters replaced by the characters read from the current source.

Returns

Int32

The number of characters that have been read. The number will be less than or equal to the buffer length, depending on whether all input characters have been read.

Exceptions

ArgumentNullException

buffer is null.

ObjectDisposedException

The StreamReader is closed.

IOException

An I/O error occurred.