Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/

Test String

Code Generator

Generated Code

$re = '/^/'; $str = 'class FinUrad { public string Kod { get; set; } public string Nazev { get; set; } public override string ToString() { return Nazev; } } <Grid Margin="20"> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> <RowDefinition Height="Auto"/> </Grid.RowDefinitions> <StackPanel Grid.Row="0" Margin="0,0,0,10"> <TextBlock Text="Jméno:"/> <TextBox x:Name="txtJmeno" Margin="0,5,0,10"/> <TextBlock Text="Rodné číslo (XXXXXX/XXXX):"/> <TextBox x:Name="txtRC" Margin="0,5,0,10"/> <TextBlock Text="Finanční úřad:"/> <ComboBox x:Name="comboFinUrady" DisplayMemberPath="Nazev" Margin="0,5,0,10"/> <TextBlock Text="Zpráva:"/> <TextBox x:Name="txtZprava" AcceptsReturn="True" Height="80" Margin="0,5,0,10"/> </StackPanel> <StackPanel Grid.Row="2" Orientation="Horizontal" HorizontalAlignment="Right"> <Button x:Name="btnZobrazitHistorii" Content="Zobrazit historii" Click="btnZobrazitHistorii_Click"/> <Button x:Name="btnOdeslat" Content="Odeslat" Click="btnOdeslat_Click"/> </StackPanel> </Grid> public partial class MainWindow : Window { private ObservableCollection<FinUrad> urady = new(); private const string ApiUrl = "https://csharp.janjanousek.cz/api/financni-urady/"; private const string ApiKey = "VSB"; public MainWindow() { InitializeComponent(); LoadFinUrady(); } private async void LoadFinUrady() { while (true) { try { using HttpClient client = new(); client.DefaultRequestHeaders.Add("x-api-key", ApiKey); var response = await client.GetAsync(ApiUrl); if (response.StatusCode == System.Net.HttpStatusCode.TooManyRequests) { if (response.Headers.TryGetValues("Retry-After", out var values)) { int secods = int.Parse(values.First()); await Task.Delay(secods * 1000); continue; } } response.EnsureSuccessStatusCode(); var xmlString = await response.Content.ReadAsStringAsync(); var xml = XDocument.Parse(xmlString); var polozky = xml.Descendants("POLOZKA"); foreach (var elem in polozky) { string id = elem.Element("CHODNOTA")?.Value; string name = elem.Element("ZKRTEXT")?.Value; if (!string.IsNullOrEmpty(id) && !string.IsNullOrEmpty(name)) { urady.Add(new FinUrad { Kod = id, Nazev = name }); } } comboFinUrady.ItemsSource = urady; comboFinUrady.SelectedIndex = 0; break; } catch (Exception ex) { MessageBox.Show("Chyba pri nacitani financnich uradu: " + ex.Message); break; } } } private void btnOdeslat_Click(object sender, RoutedEventArgs e) { string jmeno = txtJmeno.Text; string rc = txtRC.Text; var urad = comboFinUrady.SelectedItem as FinUrad; string zprava = txtZprava.Text; if(string.IsNullOrEmpty(jmeno) || string.IsNullOrEmpty(rc) || urad == null || string.IsNullOrEmpty(zprava) || zprava.Length < 10) { MessageBox.Show("Všechna pole musí být vyplněna a zpráva musí mít alespoň 10 znaků."); return; } if(!System.Text.RegularExpressions.Regex.IsMatch(rc, @"^\\d{6}/\\d{4}$")) { MessageBox.Show("Rodné číslo musí mít formát 123456/1234."); return; } SaveToDatabase(jmeno, rc, urad.Kod, urad.Nazev, zprava); new ResultsWindow().Show(); } private void btnZobrazitHistorii_Click(object sender, RoutedEventArgs e) { new ResultsWindow().Show(); } private void SaveToDatabase(string jmeno, string rc, string idUrad, string nazevUrad, string zprava) { string dbPath = "formulare.db"; if(!File.Exists(dbPath)) { using var connection = new SqliteConnection($"Data Source={dbPath}"); connection.Open(); var cmd = connection.CreateCommand(); cmd.CommandText = @" CREATE TABLE IF NOT EXISTS Formulare ( Id INTEGER PRIMARY KEY AUTOINCREMENT, Jmeno TEXT NOT NULL, RodneCislo TEXT NOT NULL, IdUrad TEXT NOT NULL, NazevUrad TEXT NOT NULL, Zprava TEXT NOT NULL )"; cmd.ExecuteNonQuery(); } using var conn = new SqliteConnection($"Data Source={dbPath}"); conn.Open(); var insert = conn.CreateCommand(); insert.CommandText = @" INSERT INTO Formulare (Jmeno, RodneCislo, IdUrad, NazevUrad, Zprava) VALUES ($jmeno, $rc, $idUrad, $nazevUrad, $zprava)"; insert.Parameters.AddWithValue("$jmeno", jmeno); insert.Parameters.AddWithValue("$rc", rc); insert.Parameters.AddWithValue("$idUrad", idUrad); insert.Parameters.AddWithValue("$nazevUrad", nazevUrad); insert.Parameters.AddWithValue("$zprava", zprava); insert.ExecuteNonQuery(); } } <Grid> <ListBox x:Name="lstHistorie"/> </Grid> public partial class ResultsWindow : Window { public ResultsWindow() { InitializeComponent(); LoadData(); } private void LoadData() { string dbPath = "formulare.db"; if (!File.Exists(dbPath)) return; using var conn = new SqliteConnection($"Data Source={dbPath}"); conn.Open(); var cmd = conn.CreateCommand(); cmd.CommandText = @" SELECT Jmeno, RodneCislo, IdUrad, NazevUrad, Zprava FROM Formulare"; using var reader = cmd.ExecuteReader(); while (reader.Read()) { lstHistorie.Items.Add($"Jméno: {reader.GetString(0)}, RČ: {reader.GetString(1)}, Úřad: {reader.GetString(2)}, Zpráva: {reader.GetString(3)}"); } } }'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($matches);

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php