StreamReader.ReadBlock Method

Definition

Overloads

ReadBlock(Char[], Int32, Int32)

Reads a specified maximum number of characters from the current stream 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:
StreamReader.cs
Source:
StreamReader.cs
Source:
StreamReader.cs

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

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

Parameters

buffer
Char[]

When this method returns, 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

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

buffer is null.

The buffer length minus index is less than count.

index or count is negative.

An I/O error occurred.

Remarks

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

The method blocks until either count characters are read, or the end of the stream has been reached. This is a blocking version of Read.

Applies to

.NET 9 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.0, 2.1
UWP 10.0

ReadBlock(Span<Char>)

Source:
StreamReader.cs
Source:
StreamReader.cs
Source:
StreamReader.cs

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

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

Parameters

buffer
Span<Char>

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

Returns

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

buffer is null.

An I/O error occurred.

Applies to

.NET 9 and other versions
Product Versions
.NET Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Standard 2.1