MSDN Library

The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

This topic has not yet been rated - Rate this topic

TextReader.ReadBlock Method

.NET Framework 1.1

Other Versions

Reads a maximum of count characters from the current stream and writes the data to buffer, beginning at index.

[Visual Basic]
Public Overridable Function ReadBlock( _
   <InteropServices.In(), _
   Out()> ByVal buffer() As Char, _
   ByVal index As Integer, _
   ByVal count As Integer _
) As Integer
[C#]
public virtual int ReadBlock(
   [
   In,
   Out
] char[] buffer,
 int index,
 int count
);
[C++]
public: virtual int ReadBlock(
   [
   In,
   Out
] __wchar_t buffer __gc[],
 int index,
 int count
);
[JScript]
public function ReadBlock(
   buffer : Char[],
 index : int,
 count : int
) : int;

Parameters

buffer: 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: The place in buffer at which to begin writing.
count: The maximum number of characters to read.

Return Value

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

Exception Type	Condition
ArgumentNullException	buffer is a null reference (Nothing in Visual Basic).
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 method blocks until either count characters are read, or all characters have been read. This is a blocking version of Read.

The following table lists examples of other typical or related I/O tasks.

To do this...	See the example in this topic...
Create a text file.	Writing Text to a File
Write to a text file.	Writing Text to a File
Read from a text file.	Reading Text from a File
Append text to a file.	Opening and Appending to a Log File File.AppendText FileInfo.AppendText
Get the size of a file.	FileInfo.Length
Get the attributes of a file.	File.GetAttributes
Set the attributes of a file.	File.SetAttributes
Determine if a file exists.	File.Exists
Read from a binary file.	Reading and Writing to a Newly Created Data File
Write to a binary file.	Reading and Writing to a Newly Created Data File

Requirements