Regular Expression for Software Testing

USING REGULAR EXPRESSIONS IN TEST DESIGN:  While writing test scenarios and test cases for respected modules functional testing, corresponding test engineer can follow BLACK BOX TESTING TECHNIQUES along with REGULAR EXPRESSIONS to save time

Regular Expression are Mathematical Notations

[0-9] = ONE DIGIT

[0-9] {6} = 6 DIGITS

EXP:  890783

[0-9] {4-8} = 4 DIGITS TO 8 DIGITS

EXP:  1234, 12345, 123456, 1234567, 12345678

([0-9]{3})|([0-9]{7}) = 3 DIGIT NUMBER OR 7 DIGIT NUMBER

EXP:  123 OR 1234567

[a-z]= ONE ALPHABET IN LOWER CASE

[a-zA-Z]= ONE ALPHABET IN LOWER CASE OR IN UPPER CASE

[a-zA-Z]{3,5} = 3 to 5 ALPHABETS IN LOWER CASE OR UPPER CASE OR BOTH

[a-zA-Z0-9] = ONE ALPHANUMERIC POSITION IN LOWER CASE OR UPPER CASE

[a-zA-Z0-9]{4,8}= 4 to 8 ALPHANUMERICS POSITIONS IN LOWER CASE OR UPPER CASE OR BOTH

EXP:

abc9 = Valid

AbzK23= Valid

123= Invalid

7849= Valid

ABc231v32= Invalid

[a-zA-Z0-9_] ONE ALPHANUMERIC IN LOWER CASE OR UPPER CASE OR (_) UNDERSCORE

SHORTER VERSION OF REGULAR EXPRESSIONS:

[a-zA-Z0-9_] = [.]

[\.] = ONE . (DOT)

[\\.] = \ OR .(DOT)

[S] = ONE S

[\S] = ONE BLANK SPACE

[A-Z][a-b] = TWO CHARACTERS WITH THE FIRST CHARACTER IN UPPER CASE AND SECOND ONE IN LOWER CASE

EXP:  Na

[A-Z][a-z] {3} = 4 CHARACTERS WITH THE FIRST CHARACTER IN UPPER CASE AND REMAINING IN LOWER CASE

EXP:  Sand

[A-Z][a-b][3,8] = 4-9 CHARACTERS WITH THE FIRST CHARACTER IN UPPER CASE AND REMAINING IN LOWER CASE

EXP:  Sand, Beast, Breeds, etc.,

[A-Z][a-z0-9]{3,8} = 4-9 POSITIONS WITH THE FIRST CHARACTER IN UPPER CASE, REMAINING ARE ALPHANUMERIC IN LOWER CASE

[A-Z][a-z][0,4] = 1-5 CHARACTERS WITH THE FIRST CHARACTER IN UPPER CASE AND REMAINING LOWER CASE

EXP:  I, Am, Cat, etc.,

[a-z]{0,10} = NO CHARACTERS TO 10 CHARACTERS IN LOWER CASE

[a-z]{0,} = NO CHARACTER TO INFINITE (ENDLESS)

[a-z]* = NO CHARACTER TO INFINITE (SHORT FORM FOR ABOVE)

[a-z]{1,} = 1 CHARACTER TO INFINITE

[a-z]+ = 1 CHARACTER TO INFINITE (SHORT FORM FOR ABOVE)

[a-z]{0,1} = NO CHARACTER TO 1 CHARACTER

[a-z]? = NO CHARACTER TO 1 CHARACTER (SHORT FORM FOR ABOVE)

[A-Z][a-z]* = FIRST ONE CHARACTER IN UPPER CASE REMAINING ALL LOWER CASE

[A-Za-z]+ = 1 OR MORE CHARACTERS WITH UPPER OR LOWER OR BOTH CASES

[\w] = SAME AS ABOVE (SHORT FORM)

[\w][\s][\w] = TWO WORDS WITH SPACE IN BETWEEN

([\w][\s]){1,} = ONE OR MORE WORDS IN UPPER OR LOWER CASE WITH SPACE IN BETWEEN (SENTENCES)

([\w][\s]?){1,} = ONE OR MORE WORDS IN UPPER OR LOWER CASE WITH ONE OR NO SPACE (SENTENCE)

(([\w][\s]?){1,}{\.}[\s]?){1,} = ONE OR MORE PARAGRAPHS WITH ONE OR MORE SENTENCES WITH ONE OR MORE WORDS IN EACH SENTENCE AND END WITH (.) FULLSTOP