I am looking Regex formula for Dart, to check either the input is matching specific any string or not which I proved. Example: input is 'butter', and proved strings are ['but','burst','bus']. The program should return false because 'but' is not equal to the 'butter'. But it is returning true as below code.
void main() {
const string = 'Can you give me a butter';
const pattern = r'(but)|(burst)|(bus)';
final regExp = RegExp(pattern);
print(regExp.hasMatch(string.toLowerCase())); //true
}
When I changed the codes as below it worked well.
void main() {
const string = 'Can you give me a But asasa';
const pattern = r'\b(but|burst|bus)\b';
final regExp = RegExp(pattern, caseSensitive: false);
print(regExp.hasMatch(string));
}
Related
class Article{
final String id;
final List<ArticleArray> arrays;
}
class ArticleArray {
final String id;
final String array;
}
TextFormField(
onChanged: (_searchinput) {
List<String> searcharray = _searchinput.split(',');
),
_articlesForDisplay = _articles.where((article){
for(int i = 0; i < article.arrays.length; i++)
{
searchinit = article.arrays[i].arrays.toLowerCase();
}
return searchinit.contains(
RegExp(//necessary code here, caseSensitive: false),
);})
basically what i am trying to do is i am trying to search
array by array like:
-Textformfields follows the user input and every time "," is entered,i
put that word into "searcharray".
-Then i initiate a search in my function(total code is not needed to write here,
i included necessary functions),i try to use "regexp" function to search for the arrays
in my article archives.
Example:
articles[0].arrays[0].array = 'a1'
articles[0].arrays[1].array = 'a2'
articles[1].arrays[0].array = 'a1'
articles[1].arrays[1].array = 'b2'
searcharray = ['a1','b2']
Here,basically what i try to do is i try to search my article arrays by every list of arrays as possible so it matches the right one. Thats what i want.
Not sure I understand your specific requirements.
Here, I define a RegExp that I try to match to at least one item of my data.
void main() {
List<String> data = ['a1','b2', 'c3', 'a4', 'a5', 'd6'];
RegExp exp = new RegExp(r"(a\d+)");
print(data.any((item) => exp.hasMatch(item)));
}
for my programm I want to use a TextField where the user can enter a zipcode (German ones). For that I tried what you can see below. If the user enters more than 5 digits every additional digit shall be deleted immediately. Of course letters are not allowed.
When I use this pattern ^[0-9]{0,5}$ on https://regex101.com/ it does what I intended to, but when I try this in JavaFX it doesn't work. But I couldn't find a solution yet.
Can anyone tell me what I did wrong?
Edit: For people, who didn't work with JavaFX yet: When the user enters just one character, the method check(String text) is called. So the result should also be true, when there are 1 to 5 digits. But not more ;-)
public class NumberTextField extends TextField{
ErrorLabel label;
NumberTextField(String text, ErrorLabel label){
setText(text);
setFont(Font.font("Calibri", 17));
setMinHeight(35);
setMinWidth(200);
setMaxWidth(200);
this.label = label;
}
NumberTextField(){}
#Override
public void replaceText(int start, int end, String text){
if(check(text)) {
super.replaceText(start, end, text);
}
}
#Override
public void replaceSelection(String text){
if(check(text)){
super.replaceSelection(text);
}
}
private boolean check(String text){
if(text.matches("^[0-9]{0,5}$")){
label.setText("Success");
label.setBlack();
return true;
} else{
return false;
}
}
You don't need to extend TextField to do this. In fact I recommend using a TextFormatter, since this is simpler to implement:
It does not require you to overwrite multiple method. You simply need to decide based on the data about the desired input, if you want to allow the change or not.
final Pattern pattern = Pattern.compile("\\d{0,5}");
TextFormatter<?> formatter = new TextFormatter<>(change -> {
if (pattern.matcher(change.getControlNewText()).matches()) {
// todo: remove error message/markup
return change; // allow this change to happen
} else {
// todo: add error message/markup
return null; // prevent change
}
});
TextField textField = new TextField();
textField.setTextFormatter(formatter);
Your original expression should be working fine, if we wish to validate a five-digits zip though, we might want to drop the 0 quantifier:
^[0-9]{5}$
^\d{5}$
For validation purposes, we might want to keep the start and end anchors, however for just testing, we can remove and see:
[0-9]{5}
\d{5}
It is likely that some other chars, would get through our inputs, which we do not wish to have.
Demo
Test
import java.util.regex.Matcher;
import java.util.regex.Pattern;
final String regex = "^[0-9]{5}$";
final String string = "01234\n"
+ "012345\n"
+ "0\n"
+ "1234";
final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
final Matcher matcher = pattern.matcher(string);
while (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}
I am using pattern matching to match file extension with my expression String for which code is as follows:-
public static enum FileExtensionPattern
{
WORDDOC_PATTERN( "([^\\s]+(\\.(?i)(txt|docx|doc))$)" ), PDF_PATTERN(
"([^\\s]+(\\.(?i)(pdf))$)" );
private String pattern = null;
FileExtensionPattern( String pattern )
{
this.pattern = pattern;
}
public String getPattern()
{
return pattern;
}
}
pattern = Pattern.compile( FileExtensionPattern.WORDDOC_PATTERN.getPattern() );
matcher = pattern.matcher( fileName );
if ( matcher.matches() )
icon = "blue-document-word.png";
when file name comes as "Home & Artifact.docx" still matcher.matches returns false.It works fine with filename with ".doc" extension.
Can you please point out what i am doing wrong.
"Home & Artifact.docx" contains spaces. Since you allow any char except whitespaces [^\s]+, this filename is not matched.
Try this instead:
(.+?(\.(?i)(txt|docx|doc))$
It is because you have spaces in filename ("Home & Artifact.docx") but your regex has [^\\s]+ which won't allow any spaces.
Use this regex instead for WORDDOC_PATTERN:
"(?i)^.+?\\.(txt|docx|doc)$"
I have to validate a string that's supposed to contain an hour number (e.g. 00 to 23).
I hence set an annotation like:
[RegularExpression("[01]?[0-9]|2[0-3]", ErrorMessage = "Error")]
public string JobStartHour {...}
Unfortunately, this regex doesn't match the inputs from 20 to 23, as it's supposed to do (IMHO).
Doesn't this RegularExpression attribute use the plain old Regex.IsMatch ?
Regex.IsMatch("22", "[01]?[0-9]|2[0-3]")
returns true...
Edit: I know, using a string isn't the best idea so as to store a number, nevertheless, this regex issue is annoying.
This pattern will work. I ran into the same thing. It has to do with using parens to correctly establish the groupings. If the RegExAttribute can't figure it out, it seems to just quit at the pipe symbol.
Here's a unit test.
[TestMethod]
public void CheckHours()
{
var pattern = "([0-1][0-9])|(2[0-3])|([0-9])";
int cnt = 0;
var hours = new string[]
{ "1","2","3","4","5","6","7","8","9",
"01","02","03","04","05","06","07","08","09",
"10","11","12","13","14","15","16","17","18","19",
"20","21","22","23" };
var attribute = new RegularExpressionAttribute(pattern);
bool isMatchOk = false;
bool isAttrOk = false;
foreach (var hour in hours)
{
isMatchOk = System.Text.RegularExpressions.Regex.IsMatch(hour, pattern);
isAttrOk = attribute.IsValid(hour);
if (isMatchOk & isAttrOk)
{ cnt += 1; }
else
{ Debug.WriteLine(hour + " / "
+ isMatchOk.ToString() + " / "
+ isAttrOk.ToString()); }
}
Assert.AreEqual(32, cnt);
}
Try this:
[RegularExpression("2[0-3]|[01]?[0-9]", ErrorMessage = "Error")]
public string JobStartHour {...}
Don't know why this regex isn't correctly interpreted, but a solution is to implement a CustomValidation, which is pretty handy.
[CustomValidation(typeof(MyCustomValidation), "Validate24Hour")]
public string JobStartHour {...}
...
public class MyCustomValidation
{
public static ValidationResult Validate24Hour(string candidate)
{
bool isValid = false;
...
if (isValid)
{
return ValidationResult.Success;
}
else
{
return new ValidationResult("Error");
}
}
}
You have to group the | to work properly.
I successfully tried, which should be exactly your regex but grouped and limited to start & end:
^([01]?[0-9]|2[0-3])$
Your named Regex.IsMatch line returns true on every expression on my machine.
I've got a wildcard pattern, perhaps "*.txt" or "POS??.dat".
I also have list of filenames in memory that I need to compare to that pattern.
How would I do that, keeping in mind I need exactly the same semantics that IO.DirectoryInfo.GetFiles(pattern) uses.
EDIT: Blindly translating this into a regex will NOT work.
I have a complete answer in code for you that's 95% like FindFiles(string).
The 5% that isn't there is the short names/long names behavior in the second note on the MSDN documentation for this function.
If you would still like to get that behavior, you'll have to complete a computation of the short name of each string you have in the input array, and then add the long name to the collection of matches if either the long or short name matches the pattern.
Here is the code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
namespace FindFilesRegEx
{
class Program
{
static void Main(string[] args)
{
string[] names = { "hello.t", "HelLo.tx", "HeLLo.txt", "HeLLo.txtsjfhs", "HeLLo.tx.sdj", "hAlLo20984.txt" };
string[] matches;
matches = FindFilesEmulator("hello.tx", names);
matches = FindFilesEmulator("H*o*.???", names);
matches = FindFilesEmulator("hello.txt", names);
matches = FindFilesEmulator("lskfjd30", names);
}
public string[] FindFilesEmulator(string pattern, string[] names)
{
List<string> matches = new List<string>();
Regex regex = FindFilesPatternToRegex.Convert(pattern);
foreach (string s in names)
{
if (regex.IsMatch(s))
{
matches.Add(s);
}
}
return matches.ToArray();
}
internal static class FindFilesPatternToRegex
{
private static Regex HasQuestionMarkRegEx = new Regex(#"\?", RegexOptions.Compiled);
private static Regex IllegalCharactersRegex = new Regex("[" + #"\/:<>|" + "\"]", RegexOptions.Compiled);
private static Regex CatchExtentionRegex = new Regex(#"^\s*.+\.([^\.]+)\s*$", RegexOptions.Compiled);
private static string NonDotCharacters = #"[^.]*";
public static Regex Convert(string pattern)
{
if (pattern == null)
{
throw new ArgumentNullException();
}
pattern = pattern.Trim();
if (pattern.Length == 0)
{
throw new ArgumentException("Pattern is empty.");
}
if(IllegalCharactersRegex.IsMatch(pattern))
{
throw new ArgumentException("Pattern contains illegal characters.");
}
bool hasExtension = CatchExtentionRegex.IsMatch(pattern);
bool matchExact = false;
if (HasQuestionMarkRegEx.IsMatch(pattern))
{
matchExact = true;
}
else if(hasExtension)
{
matchExact = CatchExtentionRegex.Match(pattern).Groups[1].Length != 3;
}
string regexString = Regex.Escape(pattern);
regexString = "^" + Regex.Replace(regexString, #"\\\*", ".*");
regexString = Regex.Replace(regexString, #"\\\?", ".");
if(!matchExact && hasExtension)
{
regexString += NonDotCharacters;
}
regexString += "$";
Regex regex = new Regex(regexString, RegexOptions.Compiled | RegexOptions.IgnoreCase);
return regex;
}
}
}
}
You can simply do this. You do not need regular expressions.
using Microsoft.VisualBasic.CompilerServices;
if (Operators.LikeString("pos123.txt", "pos?23.*", CompareMethod.Text))
{
Console.WriteLine("Filename matches pattern");
}
Or, in VB.Net,
If "pos123.txt" Like "pos?23.*" Then
Console.WriteLine("Filename matches pattern")
End If
In c# you could simulate this with an extension method. It wouldn't be exactly like VB Like, but it would be like...very cool.
You could translate the wildcards into a regular expression:
*.txt -> ^.+\.txt$
POS??.dat _> ^POS..\.dat$
Use the Regex.Escape method to escape the characters that are not wildcars into literal strings for the pattern (e.g. converting ".txt" to "\.txt").
The wildcard * translates into .+, and ? translates into .
Put ^ at the beginning of the pattern to match the beginning of the string, and $ at the end to match the end of the string.
Now you can use the Regex.IsMatch method to check if a file name matches the pattern.
Just call the Windows API function PathMatchSpecExW().
[Flags]
public enum MatchPatternFlags : uint
{
Normal = 0x00000000, // PMSF_NORMAL
Multiple = 0x00000001, // PMSF_MULTIPLE
DontStripSpaces = 0x00010000 // PMSF_DONT_STRIP_SPACES
}
class FileName
{
[DllImport("Shlwapi.dll", SetLastError = false)]
static extern int PathMatchSpecExW([MarshalAs(UnmanagedType.LPWStr)] string file,
[MarshalAs(UnmanagedType.LPWStr)] string spec,
MatchPatternFlags flags);
/*******************************************************************************
* Function: MatchPattern
*
* Description: Matches a file name against one or more file name patterns.
*
* Arguments: file - File name to check
* spec - Name pattern(s) to search foe
* flags - Flags to modify search condition (MatchPatternFlags)
*
* Return value: Returns true if name matches the pattern.
*******************************************************************************/
public static bool MatchPattern(string file, string spec, MatchPatternFlags flags)
{
if (String.IsNullOrEmpty(file))
return false;
if (String.IsNullOrEmpty(spec))
return true;
int result = PathMatchSpecExW(file, spec, flags);
return (result == 0);
}
}
Some kind of regex/glob is the way to go, but there are some subtleties; your question indicates you want identical semantics to IO.DirectoryInfo.GetFiles. That could be a challenge, because of the special cases involving 8.3 vs. long file names and the like. The whole story is on MSDN.
If you don't need an exact behavioral match, there are a couple of good SO questions:
glob pattern matching in .NET
How to implement glob in C#
For anyone who comes across this question now that it is years later, I found over at the MSDN social boards that the GetFiles() method will accept * and ? wildcard characters in the searchPattern parameter. (At least in .Net 3.5, 4.0, and 4.5)
Directory.GetFiles(string path, string searchPattern)
http://msdn.microsoft.com/en-us/library/wz42302f.aspx
Plz try the below code.
static void Main(string[] args)
{
string _wildCardPattern = "*.txt";
List<string> _fileNames = new List<string>();
_fileNames.Add("text_file.txt");
_fileNames.Add("csv_file.csv");
Console.WriteLine("\nFilenames that matches [{0}] pattern are : ", _wildCardPattern);
foreach (string _fileName in _fileNames)
{
CustomWildCardPattern _patetrn = new CustomWildCardPattern(_wildCardPattern);
if (_patetrn.IsMatch(_fileName))
{
Console.WriteLine("{0}", _fileName);
}
}
}
public class CustomWildCardPattern : Regex
{
public CustomWildCardPattern(string wildCardPattern)
: base(WildcardPatternToRegex(wildCardPattern))
{
}
public CustomWildCardPattern(string wildcardPattern, RegexOptions regexOptions)
: base(WildcardPatternToRegex(wildcardPattern), regexOptions)
{
}
private static string WildcardPatternToRegex(string wildcardPattern)
{
string patternWithWildcards = "^" + Regex.Escape(wildcardPattern).Replace("\\*", ".*");
patternWithWildcards = patternWithWildcards.Replace("\\?", ".") + "$";
return patternWithWildcards;
}
}
For searching against a specific pattern, it might be worth using File Globbing which allows you to use search patterns like you would in a .gitignore file.
See here: https://learn.microsoft.com/en-us/dotnet/core/extensions/file-globbing
This allows you to add both inclusions & exclusions to your search.
Please see below the example code snippet from the Microsoft Source above:
Matcher matcher = new Matcher();
matcher.AddIncludePatterns(new[] { "*.txt" });
IEnumerable<string> matchingFiles = matcher.GetResultsInFullPath(filepath);
The use of RegexOptions.IgnoreCase will fix it.
public class WildcardPattern : Regex {
public WildcardPattern(string wildCardPattern)
: base(ConvertPatternToRegex(wildCardPattern), RegexOptions.IgnoreCase) {
}
public WildcardPattern(string wildcardPattern, RegexOptions regexOptions)
: base(ConvertPatternToRegex(wildcardPattern), regexOptions) {
}
private static string ConvertPatternToRegex(string wildcardPattern) {
string patternWithWildcards = Regex.Escape(wildcardPattern).Replace("\\*", ".*");
patternWithWildcards = string.Concat("^", patternWithWildcards.Replace("\\?", "."), "$");
return patternWithWildcards;
}
}