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

/
/
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)l4.2" Local $sString = "// Lab 4.2" & @CRLF & _ "#include <iostream>" & @CRLF & _ "#include <string>" & @CRLF & _ "" & @CRLF & _ "using namespace std;" & @CRLF & _ "" & @CRLF & _ "string s1, s2;" & @CRLF & _ "" & @CRLF & _ "int checkChar() {" & @CRLF & _ " int i, len;" & @CRLF & _ "" & @CRLF & _ " len = s2.length();" & @CRLF & _ " for (i = 0; i < len; i++)" & @CRLF & _ " if (s2[i] - 48 < 0 || s2[i] - 48 > 9)" & @CRLF & _ " return 0;" & @CRLF & _ "" & @CRLF & _ " return 1;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "void inputString() {" & @CRLF & _ " cout << " - Nhap chuoi S1: ";" & @CRLF & _ " getline(cin, s1);" & @CRLF & _ " " & @CRLF & _ " while (1) {" & @CRLF & _ " cout << " - Nhap chuoi S2: ";" & @CRLF & _ " getline(cin, s2);" & @CRLF & _ "" & @CRLF & _ " if (!checkChar())" & @CRLF & _ " cout << " => " << "Input Validation" << endl << endl;" & @CRLF & _ " else" & @CRLF & _ " break;" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int checkNumber() {" & @CRLF & _ " int i, len;" & @CRLF & _ " len = s1.length();" & @CRLF & _ "" & @CRLF & _ " for (i = 0; i < len; i++)" & @CRLF & _ " if (s1[i] - 48 >= 0 && s1[i] - 48 <= 9)" & @CRLF & _ " return 1;" & @CRLF & _ "" & @CRLF & _ " return 0;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int checkSDTMobifone() {" & @CRLF & _ " int i, len;" & @CRLF & _ " len = s2.length();" & @CRLF & _ "" & @CRLF & _ " if (len==10 && s2[0] - 48 == 0 && s2[1] - 48 == 9 && s2[2] - 48 == 0) {" & @CRLF & _ " for (i = 3; i < 10; i++) {" & @CRLF & _ " if (s2[i] - 48 < 0 || s2[i] - 48 > 9)" & @CRLF & _ " return 0;" & @CRLF & _ " }" & @CRLF & _ " return 1;" & @CRLF & _ " }" & @CRLF & _ " else" & @CRLF & _ " return 0;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int checkSubString() {" & @CRLF & _ " int i, j;" & @CRLF & _ " int len, len_s1, len_s2, flag;" & @CRLF & _ " char temp;" & @CRLF & _ "" & @CRLF & _ " len_s1 = s1.length();" & @CRLF & _ " len_s2 = s2.length();" & @CRLF & _ "" & @CRLF & _ " if (len_s2 == 0)" & @CRLF & _ " return 1;" & @CRLF & _ "" & @CRLF & _ " if (len_s1 >= len_s2) {" & @CRLF & _ " for (i = 0; i <= len_s1 - len_s2; i++) {" & @CRLF & _ " flag = 1;" & @CRLF & _ " for (j = 0; flag&&j < len_s2; j++) {" & @CRLF & _ " if (s1[i + j] != s2[j])" & @CRLF & _ " flag = 0;" & @CRLF & _ " }" & @CRLF & _ " if (flag)" & @CRLF & _ " return 1;" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ " " & @CRLF & _ " return 0;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "string addString(){" & @CRLF & _ " string s3;" & @CRLF & _ " int i, len_s1, len_s2, len;" & @CRLF & _ "" & @CRLF & _ " len_s1 = s1.length();" & @CRLF & _ " len_s2 = s2.length();" & @CRLF & _ " len = len_s1 + len_s2;" & @CRLF & _ "" & @CRLF & _ " for (i = 0; i < len; i++) {" & @CRLF & _ " if (i < len_s1)" & @CRLF & _ " s3 += s1[i];" & @CRLF & _ " else" & @CRLF & _ " s3 += s2[i - len_s1];" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " return s3;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "void insertString(string s3) {" & @CRLF & _ " string str_Insert = "Buffer_Overflow";" & @CRLF & _ " char after;" & @CRLF & _ " int i, len, flag;" & @CRLF & _ "" & @CRLF & _ " len = s3.length();" & @CRLF & _ "" & @CRLF & _ " cout << " - Chuoi S3: " << s3 << endl;" & @CRLF & _ "" & @CRLF & _ " cout << " - Ban muon them vao sau ky tu nao: ";" & @CRLF & _ " cin >> after;" & @CRLF & _ "" & @CRLF & _ " cout << endl << " => ";" & @CRLF & _ "" & @CRLF & _ " flag = 0;" & @CRLF & _ " for (i = 0; i < len; i++) {" & @CRLF & _ " if (s3[i] != after) {" & @CRLF & _ " cout << s3[i];" & @CRLF & _ " }" & @CRLF & _ " else {" & @CRLF & _ " cout << after << str_Insert;" & @CRLF & _ " flag++;" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " if (!flag)" & @CRLF & _ " cout << str_Insert << endl;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int main() {" & @CRLF & _ "" & @CRLF & _ " string s1, s2, s3;" & @CRLF & _ " // Cau 1" & @CRLF & _ " cout << endl << "Cau 1: " << endl;" & @CRLF & _ " inputString();" & @CRLF & _ "" & @CRLF & _ " // Cau 2" & @CRLF & _ " cout << endl << "Cau 2: " << endl;" & @CRLF & _ " if (checkNumber())" & @CRLF & _ " cout << " - Chuoi S1 co chu so" << endl;" & @CRLF & _ " else" & @CRLF & _ " cout << " - Chuoi S1 khong co chu so" << endl;" & @CRLF & _ "" & @CRLF & _ " // Cau 3" & @CRLF & _ " cout << endl << "Cau 3: " << endl;" & @CRLF & _ " if (checkSDTMobifone())" & @CRLF & _ " cout << " - Chuoi S2 la SDT mang Mobifone" << endl;" & @CRLF & _ " else" & @CRLF & _ " cout << " - Chuoi S2 khong la SDT mang Mobifone" << endl;" & @CRLF & _ "" & @CRLF & _ " // Cau 4" & @CRLF & _ " cout << endl << "Cau 4: " << endl;" & @CRLF & _ " if (checkSubString())" & @CRLF & _ " cout << " - Chuoi S2 la tap con cua chuoi S1" << endl;" & @CRLF & _ " else" & @CRLF & _ " cout << " - Chuoi S2 khong la tap con cua chuoi S1" << endl;" & @CRLF & _ "" & @CRLF & _ " // Cau 5" & @CRLF & _ " cout << endl << "Cau 5: " << endl;" & @CRLF & _ " cout << " - Chuoi S3 = S1 + S2: ";" & @CRLF & _ " s3 = addString();" & @CRLF & _ " cout << s3 << endl;" & @CRLF & _ "" & @CRLF & _ " // Cau 6" & @CRLF & _ " cout << endl << "Cau 6: " << endl;" & @CRLF & _ " insertString(s3);" & @CRLF & _ " cout << endl << endl;" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ " //system("pause");" & @CRLF & _ " " & @CRLF & _ " return 0;" & @CRLF & _ "}" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm