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Valid file nameIs there a simple function to test if a string is a valid file name (i.e
does not contain illegal characters etc) other than doing it the long way? Thanks Jack Russell Hi Jack,
Simply do a check to see if file.exists if file exists it is a valid path if not path was invalid. --Or to open a file -- prompt the user with a file dialogue box. hope this helps Adam Jack Russell wrote: Show quoteHide quote > Is there a simple function to test if a string is a valid file name (i.e > does not contain illegal characters etc) other than doing it the long way? > > Thanks > > Jack Russell Adamz5 wrote:
Show quoteHide quote > Hi Jack, I tried file exists (before posting) with an invalid name - a/b.txt and > > Simply do a check to see if file.exists > > if file exists it is a valid path if not path was invalid. > > --Or to open a file -- prompt the user with a file dialogue box. > > hope this helps > > Adam > > Jack Russell wrote: > >>Is there a simple function to test if a string is a valid file name (i.e >>does not contain illegal characters etc) other than doing it the long way? >> >>Thanks >> >>Jack Russell > > it did not throw an exception (much to my surprise) Jack try this
regards Adam Imports System.IO Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click ' Dim f As File If File.Exists("c:\a/b.txt ") Then MsgBox("validpath") Else MsgBox("invalidpath") End If End Sub End Class This would report an invalid path even if the filename is syntactically
correct but just doesn't exist! Simon -- Show quoteHide quote================================ Simon Verona Dealer Management Service Ltd Stewart House Centurion Business Park Julian Way Sheffield S9 1GD Tel: 0870 080 2300 Fax: 0870 735 0011 "Adamz5" <ada***@hotmail.com> wrote in message news:1152176207.001859.17850@b68g2000cwa.googlegroups.com... > try this > > regards > > Adam > > Imports System.IO > > Public Class Form1 > > Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As > System.EventArgs) Handles Button1.Click > ' Dim f As File > > If File.Exists("c:\a/b.txt ") Then > MsgBox("validpath") > Else > MsgBox("invalidpath") > End If > > End Sub > End Class > Okay here you go...
full code to check file name. 'place a textbox on form write text into it and then press button 1 'place this code in the button1_click event to check that the filename entered in textbox 1 is fine Dim uservalue As String uservalue = TextBox1.Text Dim b As Boolean = False b = uservalue.Contains("/") Or uservalue.Contains("?") _ Or uservalue.Contains(":") _ Or uservalue.Contains("*") _ Or uservalue.Contains("""") _ Or uservalue.Contains("<") _ Or uservalue.Contains(">") _ Or uservalue.Contains("|") _ Or uservalue.Contains("?") If b = False Then MsgBox("Valid Filename") Else MsgBox("Invalid Filename") End If By the way this is the long way (not that long is it?) Anyway hope this helps Regards Adam Adamz5 wrote:
Show quoteHide quote > Okay here you go... Yes that is basically what I did but knowing MS there are other things > full code to check file name. > > > 'place a textbox on form write text into it and then press button 1 > 'place this code in the button1_click event to check that the filename > entered in textbox 1 is fine > > Dim uservalue As String > uservalue = TextBox1.Text > Dim b As Boolean = False > > b = uservalue.Contains("/") Or uservalue.Contains("?") _ > Or uservalue.Contains(":") _ > Or uservalue.Contains("*") _ > Or uservalue.Contains("""") _ > Or uservalue.Contains("<") _ > Or uservalue.Contains(">") _ > Or uservalue.Contains("|") _ > Or uservalue.Contains("?") > > If b = False Then > MsgBox("Valid Filename") > Else > MsgBox("Invalid Filename") > End If > > By the way this is the long way (not that long is it?) > > Anyway hope this helps > > Regards > > Adam > that make a file name invalid so I thought there might be a system function that checked all possibilities. Anyway thanks for everyones thoughts. Jack Hello Jack,
On XP SP1 or 2k3 there is: CheckNameLegalDOS8Dot3() exported by Kernel32.dll. It obviously does not work on long filenames.. so don't forget about GetShortPathName() -Boo Show quoteHide quote > Adamz5 wrote: > >> Okay here you go... >> full code to check file name. >> 'place a textbox on form write text into it and then press button 1 >> 'place this code in the button1_click event to check that the >> filename entered in textbox 1 is fine >> >> Dim uservalue As String >> uservalue = TextBox1.Text >> Dim b As Boolean = False >> b = uservalue.Contains("/") Or uservalue.Contains("?") _ >> Or uservalue.Contains(":") _ >> Or uservalue.Contains("*") _ >> Or uservalue.Contains("""") _ >> Or uservalue.Contains("<") _ >> Or uservalue.Contains(">") _ >> Or uservalue.Contains("|") _ >> Or uservalue.Contains("?") >> If b = False Then >> MsgBox("Valid Filename") >> Else >> MsgBox("Invalid Filename") >> End If >> By the way this is the long way (not that long is it?) >> >> Anyway hope this helps >> >> Regards >> >> Adam >> > Yes that is basically what I did but knowing MS there are other things > that make a file name invalid so I thought there might be a system > function that checked all possibilities. Anyway thanks for everyones > thoughts. > > Jack > Which version ?
2.0 has a System.IO.Path.GetFullPath that should raise an Argument exception if the path contains invalid chars (the same class exposes info about forbidden chars for file names and paths). -- Patrice "Jack Russell" <ja***@norubbish.tpg.com.au> a écrit dans le message de news: OVm9THNoGHA.4***@TK2MSFTNGP03.phx.gbl...Show quoteHide quote > Is there a simple function to test if a string is a valid file name (i.e > does not contain illegal characters etc) other than doing it the long way? > > Thanks > > Jack Russell Try Path.GetFileName or Path.GetDirectoryName (or both). Both will throw an
exception if invalid characters are found in the string. If you need a list of invalid characters you can get them by using Path.GetInvalidFileNameChars and Path.GetInvalidPathChars /claes Show quoteHide quote "Jack Russell" <ja***@norubbish.tpg.com.au> wrote in message news:OVm9THNoGHA.4172@TK2MSFTNGP03.phx.gbl... > Is there a simple function to test if a string is a valid file name (i.e > does not contain illegal characters etc) other than doing it the long way? > > Thanks > > Jack Russell Claes Bergefall wrote:
Show quoteHide quote > Try Path.GetFileName or Path.GetDirectoryName (or both). Both will throw an Thanks for that> exception if invalid characters are found in the string. If you need a list > of invalid characters you can get them by using Path.GetInvalidFileNameChars > and Path.GetInvalidPathChars > > /claes > > > "Jack Russell" <ja***@norubbish.tpg.com.au> wrote in message > news:OVm9THNoGHA.4172@TK2MSFTNGP03.phx.gbl... > >>Is there a simple function to test if a string is a valid file name (i.e >>does not contain illegal characters etc) other than doing it the long way? >> >>Thanks >> >>Jack Russell > > > Claes,
That works for some characters but not all ? and / are not valid but it does not throw an exception for them. Jack Claes Bergefall wrote: Show quoteHide quote > Try Path.GetFileName or Path.GetDirectoryName (or both). Both will throw an > exception if invalid characters are found in the string. If you need a list > of invalid characters you can get them by using Path.GetInvalidFileNameChars > and Path.GetInvalidPathChars > > /claes > > > "Jack Russell" <ja***@norubbish.tpg.com.au> wrote in message > news:OVm9THNoGHA.4172@TK2MSFTNGP03.phx.gbl... > >>Is there a simple function to test if a string is a valid file name (i.e >>does not contain illegal characters etc) other than doing it the long way? >> >>Thanks >> >>Jack Russell > > > Use the array of invalid characters from the Path class:
If fileName.IndexOfAny(System.IO.Path.GetInvalidPathChars()) <> -1 Then Jack Russell wrote: Show quoteHide quote > Is there a simple function to test if a string is a valid file name (i.e > does not contain illegal characters etc) other than doing it the long way? > > Thanks > > Jack Russell "Göran Andersson" <gu***@guffa.com> schrieb: ACK, but note that this won't guarantee the validity of the filename because > Use the array of invalid characters from the Path class: > > If fileName.IndexOfAny(System.IO.Path.GetInvalidPathChars()) <> -1 Then 'GetInvalidPathChars' doens't necessarily return all invalid path characters and even a path that doesn't contain any of these characters still may not be valid. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://classicvb.org/petition/> Göran Andersson wrote:
> Use the array of invalid characters from the Path class: This would qualify:> > If fileName.IndexOfAny(System.IO.Path.GetInvalidPathChars()) <> -1 Then > > "c:\foo\::bar:\d\\foo" as valid. The above method will only tell you if it contains invalid characters, but it will not tell you if a path is actually a valid path. -- Rinze van Huizen C-Services Holland b.v 
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