Study the code to see what happens from point to point. Note that I used a Pointer for the buffer. You can use just about any type as a buffer, but a pointer makes sense because its a simple 4-byte value. If you are copying a text file and want to treat the pointer like a string, you can cast it as a PChar, so long as you append a 0 byte to the end of the buffer.
Neat stuff, huh? TFileStream is not a direct assignment of TStream. In fact, it's a descendant of THandleStream which, when created, fills a property value called Handle which is the handle to an external file.
TFileStream inherits the Handle property. The significance of this is really neat: File operations that take a handle as input can be applied to a TFileStream. That has interesting implications in that you can do file operations on a TFileStream object before you write it to another place. Try experimenting with this. Okay, we've come a long way. And no, I haven't delved into the depths of Stream classes. That's probably best left to another article or series of articles. In any case, play around with the TCopyFile class.
It could prove to be a useful addition to your applications. How do I copy a file in Delphi? Reminiscing on Days Gone By Quick and Dirty Copying Traditionally, copying a file involves using a loop to move a series of blocks from one file into a temporary buffer, then copying the contents of the buffer into another file. CopyFrom sStream, 0 ; finally dStream. Free; end; finally sStream.
A Sexier File Copy If you write robust user interfaces, practically everything that you do involves interacting with the user by providing visual cues to let the user know what's going on.
I have found examples of CopyFileEx with progress, but I need to copy some files from a folder with overall progress. Now, gathering files from directory and calculating their total size for progress. Please note that the procedure requires an instance of TStringList class where will be stored file paths.
Experimenting with buffer size my improve performance. However it is quite fast as it is now. Also this is quick solution which I wrote few years ago for other forum, it might contain some bugs. So use at own risk ;-.
Add up the file size for all the files before you start. Then you can manually convert the progress for each individual file into an overall progress. Well, I had an answer - but I only just got around to digging it out : But here it is anyway, I wrote this a few years ago as part of a program that was called "CopyFilesAndFailGraceFully. You can call it to get a recursive filecount, filesize or Copy the files in a folder to a new folder.
Or Mod for your own situation : Anyway its an example of what you need. Its an Object As you see to use it roughly : You will need a couple of vars appropriately named. Declare your callback:. A main purpose of my soft is not copying. How are we doing? Please help us improve Stack Overflow. Take our short survey. Copying files with progress bar? REQ: File copy progress indicator 4.
Progress Bar during a large file copy? Copy progress 6. File copy progress? Progress of the Progress Bar! How Can i copy a TTreeview copy? Terry Delphi Developer. Wed, 22 Dec GMT Copy with Progress Does anybody have a example of how to copy a file or selection of files and to utilise the progress bar to show how much of the task is completed I have looked in the help file and will be referring to the manual next. There are numerous ways to copy a file from one location to another, but the most straight-forward method is by using the CopyFile method, located in the Winapi.
Windows unit While you have already accepted an answer I wanted to expand slightly. The following is Delphi 7 but it likely to be similar in other versions. Either way it might point you in the right direction. Method 1 copies the file from Oldname to Newname and displays a message indicating success or failure. I hope that helps you. Being a beginner it can be very overwhelming and sometimes you just need a helping hand.
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