Where does StreamHelper live in the IronWord API?

StreamHelper is a static class in the IronWord.Models.Extensions namespace, shipped in IronWord.dll, with base type System.Object. Its GetImageType and ToBase64 methods are extensions on stream types, available once the namespace is in scope.

How do you detect an image type from a stream in C#?

Call GetImageType on a FileStream, MemoryStream, or Stream and read the returned ImageType. Use ToBase64 on a FileStream or Stream to get a Base64 string of the same data without writing it to disk first.

Class StreamHelper

Helper class for working with streams and detecting image types.

Inheritance

System.Object

StreamHelper

Namespace: IronWord.Models.Extensions

Assembly: IronWord.dll

Syntax

public static class StreamHelper : Object

StreamHelper reads image data straight from a stream so a developer can detect a picture's format and encode it without first writing it to disk. The two methods are extensions, so they read as methods on the stream itself once the IronWord.Models.Extensions namespace is in scope. They are useful when an image arrives as an upload, a database blob, or an in-memory buffer rather than a file on disk.

GetImageType inspects the content of a stream and returns the detected format as an ImageType value (such as Png or Jpeg), with overloads for a FileStream, a MemoryStream, and a general Stream, so detection works regardless of how the bytes were obtained. ToBase64 reads a stream and returns its Base64 string, ready to embed in markup or store as text, with overloads for a FileStream and a general Stream. Each call works from the stream you already hold, so an uploaded picture can be checked for its type and converted to Base64 in the same pass before it is added to a document.

using FileStream stream = File.OpenRead("logo.png");
ImageType type = stream.GetImageType();

The add image how-to inserts a picture, and the extract images how-to reads them back out.

Methods

GetImageType(FileStream)

Determines the image type based on the content of the file stream.

Declaration

public static ImageType GetImageType(this FileStream stream)

Parameters

Type	Name	Description
System.IO.FileStream	stream	The input file stream to analyze.

Returns

Type	Description
ImageType	The detected image type.

GetImageType(MemoryStream)

Determines the image type based on the content of the stream.

Declaration

public static ImageType GetImageType(this MemoryStream stream)

Parameters

Type	Name	Description
System.IO.MemoryStream	stream	The input stream to analyze.

Returns

Type	Description
ImageType	The detected image type.

GetImageType(Stream)

Determines the image type based on the content of the stream.

Declaration

public static ImageType GetImageType(this Stream stream)

Parameters

Type	Name	Description
System.IO.Stream	stream	The input stream to analyze.

Returns

Type	Description
ImageType	The detected image type.

ToBase64(FileStream)

Converts the content of the file stream to a base64-encoded string.

Declaration

public static string ToBase64(this FileStream stream)

Parameters

Type	Name	Description
System.IO.FileStream	stream	The input file stream to convert.

Returns

Type	Description
System.String	A base64-encoded string representing the file stream content.

ToBase64(Stream)

Converts the content of the stream to a base64-encoded string.

Declaration

public static string ToBase64(this Stream stream)

Parameters

Type	Name	Description
System.IO.Stream	stream	The input stream to convert.

Returns

Type	Description
System.String	A base64-encoded string representing the stream content.