ContentRangeHeaderValue Class

Represents the value of a Content-Range header.

Namespace

System.Net.Http.Headers

Assembly

System.Net.Http.dll

Syntax

public sealed class ContentRangeHeaderValue : ICloneable

Remarks

The Content-Range header is used to indicate the range of the entity-body that is being returned in a response to a byte-range request. This header is commonly used for partial content delivery, such as resuming interrupted downloads.

A Content-Range header can be structured as follows:

Content-Range: <unit> <range-start>-<range-end>/<size>
A value of Content-Range: bytes 0-499/1000 indicates that the response contains bytes 0 through 499 of a total of 1000 bytes. A value of Content-Range: bytes */1000 indicates that the total size is 1000 bytes, but the current response does not contain a specific range.

Constructors

ContentRangeHeaderValue(long, long)

Initializes a new instance of the ContentRangeHeaderValue class with the specified start and end byte positions.

public ContentRangeHeaderValue(long from, long to);

Parameters

from
The starting byte position of the range.
to
The ending byte position of the range.

ContentRangeHeaderValue(long, long, long)

Initializes a new instance of the ContentRangeHeaderValue class with the specified start, end byte positions, and the total size of the entity-body.

public ContentRangeHeaderValue(long from, long to, long length);

Parameters

from
The starting byte position of the range.
to
The ending byte position of the range.
length
The total size of the entity-body.

Properties

From

Gets the starting byte position of the range.

public long? From { get; }

Length

Gets the total size of the entity-body. If the size is unknown, this value is null.

public long? Length { get; }

To

Gets the ending byte position of the range.

public long? To { get; }

Methods

Parse(string)

Parses a string representation of a Content-Range header value.

public static ContentRangeHeaderValue Parse(string input);

Parameters

input
A string representation of a Content-Range header value.

Returns

An instance of the ContentRangeHeaderValue class.

Exceptions

ArgumentInvalidOperationException: The string is not a valid Content-Range header value.

TryParse(string, out ContentRangeHeaderValue)

Tries to parse a string representation of a Content-Range header value.

public static bool TryParse(string input, out ContentRangeHeaderValue value);

Parameters

input
A string representation of a Content-Range header value.
value
When this method returns, contains the parsed ContentRangeHeaderValue object if the parse was successful, or null if the parse failed.

Returns

true if the string was parsed successfully; otherwise, false.

ToString()

Returns the string representation of the Content-Range header value.

public override string ToString();

Returns

The string representation of the Content-Range header value.

Examples

Creating a Content-Range Header

// Example 1: Partial content with known total size
var range1 = new ContentRangeHeaderValue(0, 499, 1000);
Console.WriteLine(range1.ToString()); // Output: bytes 0-499/1000

// Example 2: Entire content, size unknown
var range2 = new ContentRangeHeaderValue(0, 999);
range2.Length = 1000; // Setting length separately if not provided initially
Console.WriteLine(range2.ToString()); // Output: bytes 0-999/1000

// Example 3: Unknown total size (using *)
var range3 = new ContentRangeHeaderValue(500, 999);
range3.Length = null; // Indicates unknown size with '*'
Console.WriteLine(range3.ToString()); // Output: bytes 500-999/*

Parsing a Content-Range Header

string headerString = "bytes 100-199/500";
ContentRangeHeaderValue parsedRange;

if (ContentRangeHeaderValue.TryParse(headerString, out parsedRange))
{
    Console.WriteLine($"Parsed From: {parsedRange.From}"); // Output: Parsed From: 100
    Console.WriteLine($"Parsed To: {parsedRange.To}");   // Output: Parsed To: 199
    Console.WriteLine($"Parsed Length: {parsedRange.Length}"); // Output: Parsed Length: 500
}
else
{
    Console.WriteLine($"Failed to parse: {headerString}");
}

// Example with unknown size
string headerStringUnknown = "bytes */1000";
if (ContentRangeHeaderValue.TryParse(headerStringUnknown, out parsedRange))
{
    Console.WriteLine($"Parsed From: {parsedRange.From}"); // Output: Parsed From: null
    Console.WriteLine($"Parsed To: {parsedRange.To}");   // Output: Parsed To: null
    Console.WriteLine($"Parsed Length: {parsedRange.Length}"); // Output: Parsed Length: 1000
}