In order to accommodate large files, the offset is stored in the form of an unsigned long long. The following example opens a file for reading and then performs a number of method calls to move the offset to different positions, outputting the current offset after each move:. File offsets are a key aspect of working with files using the NSFileHandle class so it is worth taking extra time to make sure you understand the concept.
Without knowing where the current offset is in a file it is impossible to know where in the file data will be read or written. Once a file has been opened and assigned a file handle, the contents of that file may be read from the current offset position.
The readDataOfLength method reads a specified number of bytes of data from the file starting at the current offset. For example, the following code reads 5 bytes of data from offset 10 in a file.
The data read is returned encapsulated in an NSData object:. Alternatively, the readDataToEndOfFile method will read all the data in the file starting at the current offset and ending at the end of the file. The writeData method writes the data contained in an NSData object to the file starting at the location of the offset. Note that this does not insert data but rather overwrites any existing data in the file at the corresponding location. To see this in action we need to begin with a file.
Using a text editor, create a file named quickfox. Next, we will write a program that opens the file for updating, seeks to position 10 and then writes some data at that location:. When the above program is compiled and executed the contents of the quickfox. A file may be truncated at the specified offset using the truncateFileAtOffset method. To delete the entire contents of a file, specify an offset of 0 when calling this method:.
Jump to: navigation , search. Navigation menu Personal tools. Namespaces Page Discussion. Views Read View source View history. This page was last modified on 27 October , at Copyright Payload Media, Inc. I want to read the content of text file which is in my Resourse folder. The files in your "Resource folder" are actually the contents of your application bundle. So first you need to get the path of the file within your application bundle. As a bonus you can have different localized versions of filename.
The first thing you want to do is get the path for the text file you want to read. Since it's in your Resources folder, I'm assuming you're copying it into the main bundle of the application.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 12 years, 3 months ago. Active 6 years, 11 months ago. Viewed 63k times. I am new to iPhone Programming I want to read the content of text file which is in my Resourse folder. All that is needed to get a file in the resources and view the properties window and set the File Type to Binary. I appreciate the fact that many purists will take a look at these unit test, and regard them more as integration tests, in that the test is testing actual outcomes of a unit of work, in that there is still a dependency on LinqToCsv being present and that it does some kind of work.
However, in my case I did want the ability to test this code, and ensure that the results it emits are as expected. I also wanted a method that I could quickly and repeatedly run these tests.
I would love to hear your views on this. If you feel that you could provide me with a better solution or even improve my current solution I would certainly love to hear it, feel free to contact me or leave a note in the comment section below. Source ; return new CsvContext. Length]; resFilestream. Read ba, 0, ba. GenerateStrictMock ; stubFileDesc. Return true ; stubFileDesc. Return ';' ; stubFileDesc.
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