Regex for a valid filepath filename extension

Question

I am looking for a regex that validates a couple of things. 1.Validate is the string is a valid filepath. 2. Validate if the extension has a '.xml' extension.

Vulpes · Answer

The reason it doesn't work is because the file path contains some upper case letters and the regex you're using only allows for lower case letters. However, the regex in my first post does allow for upper and lower case letters and works fine in this case: string regExp = @"^(?:[A-Za-z]\:|\)(\[a-zA-Z_\-\s0-9\.]+)+\.xml$";

David Smith · Answer

The regex is false when I do this below. It goes into the else case which is false because that's a valid filename path extension. Something is wrong with the regex string probably var regExp = @"^(?:[\w]\:|\)(\[a-z_\-\s0-9\.]+)+\.(xml|)$"; string fileN = @"C:\Temp\Run5.xml"; Regex regex = new Regex(regExp); if (regex.IsMatch(fileN)) { } else { }

David Smith · Answer

Thanks vuples. This works.

Iftikar Hussain · Answer

Vulpes Yes you are right, it should be like this var regExp = @"^(?:[A-Za-z]\:|\)(\[a-z_\-\s0-9\.]+)+\.(xml)$"; var fileName = TxtBxFirstName.Text; Regex regex = new Regex(regExp); if (regex.IsMatch(fileName)) { MessageBox.Show("Valid File"); } else { MessageBox.Show("InValid File"); } Regards, Iftikar

Vulpes · Answer

Iftikar, That would validate some invalid file paths such as this one: 2:\my files\vulpes.xml As the drive needs to be a letter, the \w needs to be replaced by a-z and A-Z also needs including if you want it to be case insensitive, as in my own effort.

Iftikar Hussain · Answer

sorry, try this var regExp = @"^(?:[\w]\:|\)(\[a-z_\-\s0-9\.]+)+\.(xml)$"; var fileName = TxtBxFirstName.Text; Regex regex = new Regex(regExp); if (regex.IsMatch(fileName)) { MessageBox.Show("Valid File"); } else { MessageBox.Show("InValid File"); } Regards, Iftikar

Iftikar Hussain · Answer

What is your file path and file name? Can you give me example? Regards, Iftikar

David Smith · Answer

I tried this earlier. This did not work. I am going to post my code later. var regExp = @"^(?:[\w]\:|\)(\[a-z_\-\s0-9\.]+)+\.(xls|xlsx)$"; var fileName = TxtBxFirstName.Text; Regex regex = new Regex(regExp); if (regex.IsMatch(fileName)) { MessageBox.Show("Valid File"); } else { MessageBox.Show("InValid File"); }

Sanjeeb Lenka · Answer

var regExp = @" ^(?:[\w]\:|\)(\[a-z_\-\s0-9\.]+)+\.(txt|gif|pdf|doc|docx|xls|xlsx|xml)$ "; for more detail follow this link http://www.codeproject.com/Tips/216238/Regular-Expression-to-Validate-File-Path-and-Exten

Iftikar Hussain · Answer

Hi, Try this var regExp = @"^(?:[\w]\:|\)(\[a-z_\-\s0-9\.]+)+\.(xls|xlsx)$"; var fileName = TxtBxFirstName.Text; Regex regex = new Regex(regExp); if (regex.IsMatch(fileName)) { MessageBox.Show("Valid File"); } else { MessageBox.Show("InValid File"); } Matches Pattern ------------------- \100.100.10.10\Test\dummy.xls \100.100.10.10\Test\Test.2\dummy.xlsx C:\Test folder\Test Test.xls C:\Test-folder\Test_folder\Test.v2.xls Non-Matched Pattern -------------------------- \100.100.10.10\Test\fi C:\Test folder\Test_folder\.xls C:\Test folder\Test_folder\dummy.xls Regards, Iftikar

Jignesh Trivedi · Answer

hi, Please refer following link it might help you http://www.codeproject.com/Tips/216238/Regular-Expression-to-Validate-File-Path-and-Exten http://www.coderanch.com/t/551777/java/java/Validating-file-path-regex

Vulpes · Answer

Try this: string regExp = @"^(?:[A-Za-z]\:|\)(\[a-zA-Z_\-\s0-9\.]+)+\.xml$";

Regex for a valid filepath filename extension

Answers (12)