Delphi ioutils

Delphi IOUtils. Accessing and changing Directories and Files in Delphi. Lots of procedures and functions available to use. IOUtils, System. Types; TDirectory - Any directory related operation 1.

Create a new Diretory TDirectory. Delete an existing directory TDirectory. Check if Directory exists TDirectory. Copy a Directory from One folder to another TDirectory. Move a Directory from One folder to another TDirectory.

delphi ioutils

Find create time, last opened time and last modified time TDirectory. Get list of in a Directory procedure TForm1. Add strFiles[i] ; end; 7. Get list of Folder in Directory procedure TForm1. Add strFiles[i] ; end; 8. Get list of logical drives in our system procedure TForm1.

Add strFiles[i] ; end; 9. TXT' ; 3. TXT' ; 4. TXT' ; 5. TXT' ; 6. TXT' ; 7. Write some data to file. TXT','' ; 8. Check for Derive exists TPath.

Get Temp Path TPath. GetTempPath; 3. GetRandomFileName; 4. Get file extension TPath. Get file name with or without extension TPath. TXT' ; TPath.

Get root path TPath.Glad to hear that it helped you. And also thanks for the proposed changes you for office as it will help others lot. I have been trying to read from Excel and used this information as the basis for a test program.

Has anyone else had this and been able to solve it? The crash is at function TExcelApplication. Windows, Winapi. Messages, System. SysUtils, System. Variants, System. Classes, Vcl. Graphics, Vcl. Controls, Vcl. Forms, Vcl. Dialogs, Excel, Vcl. StdCtrls, Vcl. Create; with FileOpenDialog1. Disconnect; myxlApp. Item[R,C]; end; procedure TForm1. Forgot to mention that I am using Delphi Any pointers would be appreciated. Your blog is very nice and provide me informative content thanks for sharing for more information about Copy Worksheet.

I put this very usefull Web page in my favorite, it is kicker to find at any time Post a Comment.

TortoiseSVN Add-In for Delphi

MS Excel Automation in Delphi. In this blog I will describe how to read and write data from and to an Excel file. For this Excel or later should have installed in our system. First use Excel unit to uses clause. This unit comes with Delphi installation it self. You can get the unit in installed path. So what it LCID? LCID: Cardinal. And now following are the codes used to access, read, write and format an Excel file.

First declare following variables FreeAndNil myxlApp. ConnectTo myxlApp.Commons-IO contains utility classesendian classesline iteratorfile filtersfile comparators and stream implementations.

For a more detailed descriptions, take a look at the javadocs. IOUtils contains utility methods dealing with reading, writing and copying. As an example, consider the task of reading bytes from a URL, and printing them. This would typically done like this:.

In certain application domains, such IO operations are common, and this class can save a great deal of time. And you can rely on well-tested code.

For utility code such as this, flexibility and speed are of primary importance. However you should also understand the limitations of this approach. Using the above technique to read a 1GB file would result in an attempt to create a 1GB String object! The FileUtils class contains utility methods for working with File objects. These include reading, writing, copying and comparing files. The FilenameUtils class contains utility methods for working with filenames without using File objects.

The class aims to be consistent between Unix and Windows, to aid transitions between these environments such as moving from development to production. The FileSystemUtils class contains utility methods for working with the file system to access functionality not supported by the JDK.

Currently, the only method is to get the free space on a drive. Note that this uses the command line, not native code. Different computer architectures adopt different conventions for byte ordering. In so-called "Little Endian" architectures eg Intelthe low-order byte is stored in memory at the lowest address, and subsequent bytes at higher addresses.

For "Big Endian" architectures eg Motorolathe situation is reversed. The org. LineIterator class provides a flexible way for working with a line-based file. The recommended usage pattern is:.

FileFilter and java. Besides that the package offers a series of ready-to-use implementations of the IOFileFilter interface including implementation that allow you to combine other such filters. These filters can be used to list files or in FileDialog, for example. See the filefilter package javadoc for more details. Comparator implementations for java. These comparators can be used to sort lists and arrays of files, for example. See the comparator package javadoc for more details.

These include:. See the input or output package javadoc for more details. All Rights Reserved. User guide Commons-IO contains utility classesendian classesline iteratorfile filtersfile comparators and stream implementations.

FilenameUtils The FilenameUtils class contains utility methods for working with filenames without using File objects. Endian classes Different computer architectures adopt different conventions for byte ordering. There are two classes in this package of relevance: The EndianUtils class contains static methods for swapping the Endian-ness of Java primitives and streams.

With this, one can read data from files of non-native Endian-ness. Line iterator The org. File filters The org.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. When I first saw the System. IOUtils unit with functions like TFile. ReadAllBytes and TFile.

Classes I was quite excited to have easy ways to read binary and text files. After using them for a while I noticed that the default share mode is implicitly fmShareCompatsince they all use TFileStream.

delphi ioutils

Createbut do not explicitly specify a share mode. Since fmShareCompat is treated as fmShareExclusive on Windows this leads to file locking problems when using them. Is this an oversight by the Delphi developers? Or is there a reason to not use fmShareDenyWrite by default? I am now tempted to write my own version of these classes in order to make them more sharing friendly.

Learn more. Why do the System. Ask Question. Asked 5 years, 11 months ago. Active 5 years, 11 months ago. Viewed times. Also why is there no way to specify a share mode? IIRC this is a giant balls up perpetrated by Emba.

Recent releases fix this. Active Oldest Votes. Sign up or log in Sign up using Google. Sign up using Facebook.

delphi ioutils

Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Socializing with co-workers while social distancing. Podcast Programming tutorials can be a real drag. Featured on Meta. Community and Moderator guidelines for escalating issues via new response….

Feedback on Q2 Community Roadmap. Triage needs to be fixed urgently, and users need to be notified upon….Delphi has long had various functions to let you work with the file system, but one of the new features of Delphi are some nice wrappers for working with files, paths and directories.

First we check if the path provided in the edtPath edit box exists. Assuming it does, we then use a for. If you look a little further in IOUtils. We implement the TFilterPredicate anonymous method to check that each file matches a wildcard pattern and that it also has its Archive flag set.

We can then pass it into our call to TDirectory. GetFiles and our code in the for. This is all fine for a single directory, but what if we want to walk over the full tree of directories? Easy, just alter our code to look like this:. We add another for. This one for each Directory in TDirectory. The second parameter indicates whether we only want to get the top level directories in the path we specify, or whether we want to do all directoriesall the way down.

The Third parameter is actually another TDirectory. One thing to note, TDirectory. IOUtils looks to be a really powerful unit, and is well worth a little playing to get familiar with it. Twitter Comment. Exists …. I think that IOUtils contains the. NET System. For me, the value of the enumerators and the filter predicates outweighs any squeemishness I might have.

IO examples that I might try and adapt. First congratulations. This is a quite good step towards the real OOP Delphi. I hope we will see soon stuff like TInt32, TString, etc.

I am so sick with the MS. Size TFile. GetVersion TFile.

Delphi Programming Tutorial #58 - TDataSetField

Exists TFile. Copy TFile. Rename TFile. Move TFile. Delete TFile. Read TFile. GetFileName TFile. GetTitle TFile. GetExtension TFile. Exists TDirectory.Class methods in records are used to group different methods into a common namespace.

Thus you can have similar named methods for different purposes. For an example in IOUtils. The older approach was to have distinct function names for FileExists and DirectoryExists which the implementations actually call.

While class methods inside classes can be used in the same way, they can in addition have another goal: they can be virtual. Called from a class variable this can lead to different implementations depending on the current content of that variable.

This is not possible for records. As a consequence class methods in records are always static. I just started to play with the new unit in Delphi IOUtils. Is there any benefits of doing that inside records instead of classes?

In both cases there's no need for any variables or instance, but I'm not sure if there any real benefits regarding memory consuming or performance improvement. I would say that the first question to ask is "Why put such functions inside either a record or a class? The use of record methods as in IOUtils is in many cases largely arbitrary in Delphi and in part reflects a fetish with following conventions in other languages that are not directly relevant in Delphi.

In some languages Java and. That is, procedures and functions cannot exist independently of any container class. Hence in those languages if you have functions and procedures they must be contained in a class. If they do not operate on member data then obviously they are declared as class methods to avoid having to construct an instance merely to call what is in fact a classLESS function. Exists s and TFile. Exists s are syntactic alternatives to DirectoryExists s and FileExists s.

In Delphi first class functions are supported and there is therefore no real reason to use classes or records to discriminate between functions, except as a way of facilitating ease of reference for a developer when writing code and using IDE assistance to browse for available methods. With a container record, you only have to know that there is a type TDirectoryand the IDE via code completion suggestions can then present all of the "methods" available for TDirectory operations.

However, in Delphi there is an alternative made possible by the support for first class functions. Rather than using arbitrary and artificial "containers", you or rather the authors of IOUtils could instead have chosen to use the existing container - a Delphi "unit":.

This still enjoys the benefits of IDE support in the form of code completion suggestions and also provides the namespace separation required to support identical function names operating on different things.

The downside of this approach and it is a big one is that where a unit uses both IOUtils. File and IOUtils. Directoryit must qualify one or other function name to avoid confusion, but this qualification could be omitted, which is why it is so dangerous:. Directory and need not qualify and repeat that fact anywhere other than in the uses clause. Filethen this could easily lead to scoping errors on any unqualified references.

For those reasons, the design choice in IOUtils at least is understandable and arguably a good one, tho ymmv. The unit that the functions must reside in may itself provide all the grouping behaviour you need.


I suspect that there may be a small static memory benefit to using a record rather than a class when fabricating these arbitrary containers.

I imagine that a class has additional overhead, tho this is going to be relatively small and static in nature i. If a class method is implemented inside a record, there is less overhead. Any class declaration requires an additional structure for class info in memory. Records does not have the structure. Class methods in Record vs Class in Delphi 3 Class methods in records are used to group different methods into a common namespace.

Rather than using arbitrary and artificial "containers", you or rather the authors of IOUtils could instead have chosen to use the existing container - a Delphi "unit": unit IOUtils.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. In IOUtils. For example IOUtils. In Embarcadero's code, CreateDirectory just raises an error. I can't use any of the functions in IOUtils. For example: My program needs to process some data in a folder and put the result back there and errors can appear quite often because of accidental wrong permissions on that folder.

The program has a lot of processing to do so it would be unreasonable for its user to let it work over night and find it in the morning stuck at 0. A log will show the failed operation. Other application is a console app. Again, it needs to move on in case of an error. A simple writeln would be sufficient to display the message.

I have my full blown library that does what IOUtils does but when possible without raising errors. Just think at it as a GUI-less application or an application that runs unsupervised so nobody would care what is the reason for which it failed one possible example would be a Service. So, is my design wrong? Why did Embarcadero choose to raise errors instead of using Boolean returning functions?

Isn't this wrong? How are they sure that the path was invalid? What if the path was correct but the drive was disconnected, or took fire?

Or the folder is locked? Or other possible reasons I could came up with? The library still has old For example TDirectory. How are we doing? Please help us improve Stack Overflow. Take our short survey. Learn more. Asked 6 years, 1 month ago.

IOUtils.pas – OO File System Access in Delphi 2010

Active 6 years, 1 month ago. Viewed times. A log will show the failed operation Other application is a console app. Update This is how Embarcadero proposes to use their unit: procedure TForm1. Delete edSourcePath. Update 2: The library still has old

thoughts on “Delphi ioutils”

Leave a Reply

Your email address will not be published. Required fields are marked *