init(contentsOfFile:)
Creates and returns an image representation object using the contents of the specified file.
Declaration
init?(contentsOfFile filename: String)Parameters
- filename:
A full or relative pathname specifying the file to open. This string should include the filename extension.
Return Value
An initialized instance of an NSImageRep subclass, or nil if the image data could not be read.
Discussion
If sent to the NSImageRep class object, this method returns a newly allocated instance of a subclass of NSImageRep (chosen through the use of class(forFileType:)) initialized with the contents of the specified file. If sent to a subclass of NSImageRep that recognizes the type of data in the file, it returns an instance of that subclass initialized with the contents of the file.
This method returns nil in any of the following cases:
The message is sent to the
NSImageRepclass object and there are no subclasses in theNSImageRepclass registry that handle the type of data in the specified file.The message is sent to a subclass of
NSImageRepand that subclass cannot handle the type of data in the specified file.The
NSImageRepsubclass is unable to initialize itself with the contents of the specified file.
The NSImageRep subclass is initialized by creating an NSData object based on the contents of the file and passing it to the imageRepWithData: method. By default, the files handled include those with the extensions “tiff”, “gif”, “jpg”, “pict”, “pdf”, and “eps”.