I'm something of a n00b at C# and I'm having trouble finding an answer to this, so if it's already been answered somewhere feel free to laugh at me (provided you also share the solution). :)
I'm reading an XML file into a GUI form, where certain elements are paths to files that are entered into TextBox objects. I'm looping through the controls on the form, and for each file path in each TextBox (lol there's like 20 of them on this form), I want to use File.Exists() to ensure it's a valid file.
The problem with this is that the file path can potentially contain spaces, and can potentially be valid; however File.Exists() is telling me it's invalid, based entirely on the spaces. Obviously I can't hard-code them and do something like
if (File.Exists(#"c:\Path To Stuff"))
and I tried surrounding the path with ", like
if (File.Exists("\"" + contentsOfTextBox + "\""))
but that didn't make a difference. Is there some way to do this? Can I escape the spaces somehow?
Thank you for your time. :)
File.Exists works just fine with spaces. There is something else giving you a problem I'll wager.
Make sure your XML reader isn't failing to read the filename (parts of XML do not allow spaces and some readers will throw an exception if they encounter one).
#"c:\Path To Stuff"
The above could be a directory not a file!
Hence you would want to use Directory.Exists!
#"c:\Path To Stuff\file.txt"
If you did have a file on the end of the path then you would use File.Exists!
As the answer said, File.Exists works with spaces, if you are checking for existence of a Directory however, you should be using Directory.Exists
What is the exact error that you get when File.Exists says it is invalid?
I suspect that you are passing a path to a directory and not a file, which will return false. If so, to check the presence of a directory, use Directory.Exists.
To echo Ron Warholic: make sure the process has permissions over the target folder. I just ran into the same "bug" and it turned out to be a permissions issue.
Did you remember to replace \ with \\ ?
You need to use youtStringValue.Trim() to remove spaces leading/trailing, and Replace to remove spaces in the string you do not want.
Also, rather use System.IO.Path.Combine rather to combine these strings.
You can use # on string variables:
string aPath = "c:\Path To Stuff\text.txt";
File.Exists(#aPath);
That should solve any escape character problems because I don't think this really looks like the spaces being the problem.
hi this is not difficult if you can convert the name of the path to a string array then go through one by one and remove the spaces
once that is done just write() to the screen where you have the files, if it is xml then your xmlmapper will suffice
file.exists() should only be used in certain circumstances if you know that it does exist but not when there can be space chars or any other possible user input
Related
I need to be able to extract the full file path out of this string (without whatever is after the file extension):
$/FilePath/FilePath/KeepsGoing/Folder/Script.sql (CS: 123456)
A simple solution such as the following could would work for this case, however it is only limited to a file extension with 3 characters:
(\$.*\..{3})
However, I find problems with this when the file contains multiple dots:
$/FilePath/FilePath/File.Setup.Task.exe.config (CS: 123456)
I need to be able to capture the full file path (from $ to the end of whatever the file extension is, which can be any number of things). I need to be able to get this no matter how many dots are in the name of the file. In some cases there are spaces in the name of the file too, so I need to be able to incorporate that.
Edit: The ending (CS....) in this case is not standard. All kinds of stuff can follow the path so I cannot predict what will come after the path, but the path will always be first. Sometimes spaces do exist in the file name.
Any suggestions?
Try this:
(\$.*\.[\w.-]+)
But! it will not properly match files with space or special chars in the file extension. If you need to match files that might have special chars in the file extension you'll need to elaborate on the input (is it quoted? is it escaped?).
I asked a similar question recently about using regex to retrieve a URL or folder path from a string. I was looking at this comment by Dour High Arch, where he says:
"I recommend you do not use regexes at all; use separate code paths
for URLs, using the Uri class, and file paths, using the FileInfo
class. These classes already handle parsing, matching, extracting
components, and so on."
I never really tried this, but now I am looking into it and can't figure out if what he said actually is useful to what I'm trying to accomplish.
I want to be able to parse a string message that could be something like:
"I placed the files on the server at http://www.thewebsite.com/NewStuff, they can also
be reached on your local network drives at J:\Downloads\NewStuff"
And extract out the two strings http://www.thewebsite.com/ and J:\Downloads\NewStuff. I don't see any methods on the Uri or FileInfo class that parse a Uri or FileInfo object from a string like I think Dour High Arch was implying.
Is there something I'm missing about using the Uri or FileInfo class that will allow this behavior? If not is there some other class in the framework that does this?
I'd say the easiest way is splitting the strings into parts first.
First delimiter would be spaces, for each word - second would be qoutes (double and single)
Then use Uri.IsWellFormedUriString on each token.
So something like:
foreach(var part in String.Split(new char[]{''', '"', ' '}, someRandomText))
{
if(Uri.IsWellFormedUriString(part, UriKind.RelativeOrAbsolute))
doSomethingWith(part);
}
Just saw at URI.IseWellFormedURIString that this is a bit to strickt to suit your needs maybe.
It returns false if www.Whatever.com is missing the http://
It was not clear from your earlier question that you wanted to extract URL and file path substrings from larger strings. In that case, neither Uri.IsWellFormedUriString nor rRegex.Match will do what you want. Indeed, I do not think any simple method can do what you want because you will have to define rules for ambiguous strings like httX://wasThatAUriScheme/andAre/these part/of/aURL or/are they/separate.strings?andIsThis%20a%20Param?
My suggestion is to define a recursive descent parser and create states for each substring you need to distinguish.
U can use :
(?<type>[^ ]+?:)(?<path>//[^ ]*|\\.+\\[^ ]*)
that will give you 2 groups on each result
type : "http:"
path : //www.thewebsite.com/NewStuff
and
type : "J:"
path : \Downloads\NewStuff
out of the string
"I placed the files on the server at
http://www.thewebsite.com/NewStuff, they can also be reached on your
local network drives at J:\Downloads\NewStuff"
you can use the "type" group to see if the type is http:or not and set action on that.
EDIT
or use regex below if you are sure there is no whitespace in your filepath :
(?<type>[^ ]+?:)(?<path>//[^ ]*|\\[^ ]*)
Try \w+:\S+ and see how well that fits your purposes.
In the file upload function that I am working on it, one important issue is to have the path where I can save the image user uploaded. In the following code, I already specified the folder within the web-based application folder for saving the uploaded files. My instructor told me that I still have a security hole with these following lines in the code-behind of asp.net UploadFile control and I don't know why!!!
string path = #"~\Images\";
string comPath = Server.MapPath(path + "\\" + FileUpload1.FileName);
Could you please tell me how to prevent this kind of security hole?
UPDATE:
Could anyone tell me how to avoid this kind of security hole? I am still trying to find something to make these two lines secure.
My instructor told me that I still have a security hole with these following lines in the code-behind of asp.net UploadFile control and I don't know why!!!
Imagine what would happen if the client send something like ..\..\foo.jpg as file name.
A fairly simple fix is to make sure the file name has no \ or / characters in it, by stripping away everything up to the first such character. (This is a good idea anyway, since browsers vary in their treatment of upload file names: some will send the full path, some just the plain file name and some may even send a fake path instead.)
The easy way to do this is with a Regex:
string fileName = Regex.Replace( FileUpload1.FileName, #"(?s)^.*[\\/]", "" );
Note that, depending on your OS and file system, there are other characters that could potentially cause problems as well. The safest option, in general, is to strip away all characters except those you know are safe, something like this:
string safeFileName = Regex.Replace( fileName, #"[^A-Za-z0-9\-._() ]", "" );
You may also want to further ensure that the file name has an extension that matches the type you expect the file to have.
There is a little confusion in my mind about server.mappath
which is correct and what's the difference betwwen these two
FileUpload1.saveAs(Server.MapPath("~/User/images/")+"ankush.jpg"));
FileUpload1.saveAs(Server.MapPath("~/User/images")+"ankush.jpg"));
The correct way of using MapPath() would be:
FileUpload1.saveAs(Server.MapPath("~/User/images/ankush.jpg"));
or if you insist:
FileUpload1.saveAs(Path.Combine(Server.MapPath("~/User/images"),"ankush.jpg")));
MapPath() doesn't append a trailing backslash to the mapped path because it has no way of knowing if the path is a directory or a file (it doesn't check if the given path actually exists)
I would advise you to use this way
FileUpload1.saveAs(Server.MapPath("~/User/images/ankush.jpg"));
Reason : because if you already know the path then why break down the filename separately
If the filename was getting passed by parameter then you could do
FileUpload1.saveAs(Server.MapPath(String.Format("~/User/images/{0}", fileName)));
What's the best way to get a string containing a folder name that I can be certain does not exist? That is, if I call DirectoryInfo.Exists for the given path, it should return false.
EDIT: The reason behind it is I am writing a test for an error checker, the error checker tests whether the path exists, so I wondered aloud on the best way to get a path that doesn't exist.
Name it after a GUID - just take out the illegal characters.
There isn't really any way to do precisely what you way you want to do. If you think about it, you see that even after the call to DirectoryInfo.Exists has returned false, some other program could have gone ahead and created the directory - this is a race condition.
The normal method to handle this is to create a new temporary directory - if the creation succeeds, then you know it hadn't existed before you created it.
Well, without creating the directory, all you can be sure of is that it didn't exist a few microseconds ago. Here's one approach that might be close enough:
string path = Path.GetTempFileName();
File.Delete(path);
Directory.CreateDirectory(path);
Note that this creates the directory to block against thread races (i.e. another process/thread stealing the directory from under you).
What I ended up using:
using System.IO;
string path = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
(Also, it doesn't seem like you need to strip out chars from a guid - they generate legal filenames)
Well, one good bet will be to concatenate strings like the user name, today's date, and time down to the millisecond.
I'm curious though: Why would you want to do this? What should it be for?
Is this to create a temporary folder or something? I often use Guid.NewGuid to get a string to use for the folder name that you want to be sure does not already exist.
I think you can be close enough:
string directoryName = Guid.NewGuid.ToSrtring();
Since Guid's are fairly random you should not get 2 dirs the same.
Using a freshly generated GUID within a namespace that is also somewhat unique (for example, the name of your application/product) should get you what you want. For example, the following code is extremely unlikely to fail:
string ParentPath = System.IO.Path.Combine(Environment.GetEnvironmentVariable("TEMP"), "MyAppName");
string UniquePath = System.IO.Path.Combine(ParentPath, Guid.NewGuid().ToString());
System.IO.Directory.CreateDirectory(UniquePath);