| Expression |
Description |
Example |
| Modifiers |
| g |
Perform a global match (find all matches rather than stopping after the first match) |
var str = "Is this all there is?";
var patt1 = /is/g;
var result = str.match(patt1);
alert(result); // result:is,is
|
| i |
Perform case-insensitive matching |
var str = "Visit W3Schools";
var patt1 = /w3schools/i;
var result = str.match(patt1);
alert(result); result:// W3Schools
|
| m |
Perform multiline matching |
var str = "\nIs th\nis it?";
var patt1 = /^is/m;
var result = str.match(patt1);
alert(result) // result://is
|
| Brackets |
| [abc] |
Find any character between the brackets |
|
| [^abc] |
Find any character NOT between the brackets |
|
| [0-9] |
Find any character between the brackets (any digit) |
|
| [^0-9] |
Find any character NOT between the brackets (any non-digit) |
|
| (x|y) |
Find any of the alternatives specified |
|
| Metacharacters |
| . |
Find a single character, except newline or line terminator |
var str = "That's hot!";
var patt1 = /h.t/g;
var result = str.match(patt1);
alert(result);// result:hat,hot
|
| \w |
Find a word character |
var str = "Give 100%!";
var patt1 = /\w/g;
var result = str.match(patt1);
alert(result); //G,i,v,e,1,0,0
|
| \W |
Find a non-word character |
var str = "Give 100%!";
var patt1 = /\W/g;
var result = str.match(patt1);
alert(result); // ,%,!
|
| \d |
Find a digit |
var str = "Give 100%!";
var patt1 = /\d/g;
var result = str.match(patt1);
alert(result); // 1,0,0
|
| \D |
Find a non-digit character |
var str = "Give 100%!";
var patt1 = /\D/g;
var result = str.match(patt1);
alert(result); // G,i,v,e, ,%,!
|
| \s |
Find a whitespace character |
var str = "Is this all there is?";
var patt1 = /\s/g;
var result = str.match(patt1);
alert(result); // , , ,
|
| \S |
Find a non-whitespace character |
var str = "Is this all there is?";
var patt1 = /\S/g;
var result = str.match(patt1); //I,s,t,h,i,s,a,l,l,t,h,e,r,e,i,s,?
|
| \b |
Find a match at the beginning/end of a word |
var str = "Visit W3Schools";
var patt1 = /\bW3/g;
var result = str.match(patt1); //W3
|
| \B |
Find a match not at the beginning/end of a word |
var str = "Visit W3Schools";
var patt1 = /\BSchool/g;
var result = str.match(patt1); // School
|
| \0 |
Find a NUL character |
var str = "Visit W3Schools.\0Learn JavaScript.";
var patt1 = /\0/;
var result = str.search(patt1); //16
|
| \n |
Find a new line character |
var str = "Visit W3Schools.\nLearn JavaScript.";
var patt1 = /\n/;
var result = str.search(patt1); //16
|
| \f |
Find a form feed character |
var str = "Visit W3Schools.\fLearn JavaScript.";
var patt1 = /\f/;
var result = str.search(patt1); // 16
|
| \r |
Find a carriage return character |
|
| \t |
Find a tab character |
|
| \v |
Find a vertical tab character |
|
| \xxx |
Find the character specified by an octal number xxx |
|
| \xdd |
Find the character specified by a hexadecimal number dd |
|
| \udddd |
Find the Unicode character specified by a hexadecimal number dddd |
|
| Quantifiers |
| n+ |
Matches any string that contains at least one n |
var str = "Hellooo World! Hello W3Schools!";
var patt1 = /o+/g;
var result = str.match(patt1);
alert(result);// result:ooo,o,o,oo
|
| n* |
Matches any string that contains zero or more occurrences of n |
var str = "Hellooo World! Hello W3Schools!";
var patt1 = /lo*/g;
var result = str.match(patt1);
alert(result);// result:l,looo,l,l,lo,l
|
| n? |
Matches any string that contains zero or one occurrences of n |
var str = "1, 100 or 1000?";
var patt1 = /10?/g;
var result = str.match(patt1);
alert(result);// result:1,10,10
|
| n{X} |
Matches any string that contains a sequence of X n's |
|
| n{X,Y} |
Matches any string that contains a sequence of X to Y n's |
var str = "100, 1000 or 10000?";
var patt1 = /\d{3,4}/g;
var result = str.match(patt1)
alert();// result:100,1000,1000
|
| n{X,} |
Matches any string that contains a sequence of at least X n's |
|
| n$ |
Matches any string with n at the end of it |
var str = "Is this his";
var patt1 = /is$/g;
var result = str.match(patt1);
alert(result);// result:is
|
| ^n |
Matches any string with n at the beginning of it |
|
| ?=n |
Matches any string that is followed by a specific string n |
var str = "Is this all there is";
var patt1 = /is(?= all)/;
var result = str.match(patt1);
alert(); // result:is
|
| ?!n |
Matches any string that is not followed by a specific string n |
var str = "Is this all there is";
var patt1 = /is(?! all)/gi;
var result = str.match(patt1);
alert(result); //result:Is,is
|
| Object Properties |
| constructor |
Returns the function that created the RegExp object's prototype |
var patt = new RegExp("Hello World", "g");
var res = patt.constructor;
alert(res) //result: function RegExp() { [native code] }
|
| global |
Checks whether the "g" modifier is set |
var str = "Visit W3Schools!";
var patt1 = /W3S/g;
var res = patt1.global;
alert();// result:true
|
| ignoreCase |
Checks whether the "i" modifier is set |
var str = "Visit W3Schools!";
var patt1 = /W3S/i;
var res = patt1.ignoreCase;
alert(res);// result:true
|
| lastIndex |
Specifies the index at which to start the next match |
var str = "The rain in Spain stays mainly in the plain";
var patt1 = /ain/g;
var res = patt1.lastIndex;
alert(res); // result :8,17,28,43
|
| multiline |
Checks whether the "m" modifier is set |
|
| source |
Returns the text of the RegExp pattern |
var str = "Visit W3Schools";
var patt1 = /W3S/g;
alert(patt1.source);// result:W3S
|
| Object Methods |
| compile() |
Deprecated in version 1.5. Compiles a regular expression |
|
| exec() |
Tests for a match in a string. Returns the first match |
var str = "The best things in life are free";
var patt = new RegExp("e");
var res = patt.exec(str); // e
|
| test() |
Tests for a match in a string. Returns true or false |
var str = "The best things in life are free";
var patt = new RegExp("e");
var res = patt.test(str);
alert(res)// result:true
|
| toString() |
Returns the string value of the regular expression |
var patt = new RegExp("Hello World", "g");
var res = patt.toString();
alert(res);// result:/Hello World/g
|
