Regular Expressions MCQs with Explanations

[:alpha:] is nothing but Lowercase and uppercase alphabetical characters.

ereg(), ereg_replace(), eregi(), eregi_replace(), split(), spliti(), and sql_regcase() are the functions offered.

Because the provided username is not all lowercase, ereg() will not return FALSE (instead returning the length of the matched string, which PHP will treat as TRUE), causing the message to output.

The split() function divides a string into various elements, with the boundaries of each element based on the occurrence of a defined pattern within the string.

This matches f followed by two to four occurrences of o.

/A, /b and /B are metacharacters. A: Matches only at the beginning of the string. b: Matches a word boundary. B: Matches anything but a word boundary.

The functions are preg_filter(), preg_grep(), preg_match(), preg_match_all(), preg_quote(), preg_replace(), preg_replace_callback(), and preg_split().

This function is used to search an array for foods beginning with s.

All of the functions mentioned above can be used to compare strings in some or the other way.

Its prototype follows string strtoupper(string str).

The str_pad() function pads a string with a specified number of characters.

The str_replace() function case sensitively replaces all instances of a string with another.

The strstr() function returns the remainder of a string beginning with the first occurrence of a predefined string.

The preg_grep function is used to search an array for specific patterns and then return a new array based on that filtering.

When we include PREG_GREP_INVERT, this will invert our data, so instead of outputting numbers it will output our non-numeric values.

The function returns 1 if search was successful else returns 0.

The code uses preg_match to check for a keyword and replies based on whether it is true (1) or false (0).

Coffee was not replaced because the preg_replace function is case sensitive. Therefore it treats coffee and Coffee differently.

The string is broken up into different values in the array based upon your input.

We use a ‘.’ period to split the data, therefor giving each sentence it’s own array entry.

The function preg_matchall does not exist. preg_match_all is a preg function.

1 and 4 is the correct answer to “PHP has long supported two regular expression implementations known as _______ and _______. 1. Perl 2. PEAR 3. Pearl 4. POSIX”. This question is standard in competitive examination syllabi for Regular Expressions.

P? is the correct answer to “Which one of the following regular expression matches any string containing zero or one p”. This question is standard in competitive examination syllabi for Regular Expressions.

PHP 5.3 is the correct answer to “POSIX implementation was deprecated in which version of PHP”. This question is standard in competitive examination syllabi for Regular Expressions.

Portable Operating System Interface for Unix is the correct answer to “POSIX stands for”. This question is standard in competitive examination syllabi for Regular Expressions.

implode() is the correct answer to “Which one of the following functions can be used to concatenate array elements to form a single delimited string”. This question is standard in competitive examination syllabi for Regular Expressions.

strrpos() is the correct answer to “Which one of the following functions finds the last occurrence of a string, returning its numerical position”. This question is standard in competitive examination syllabi for Regular Expressions.

preg_replace() is the correct answer to “Which one of the following preg PHP function is used to do a find and replace on a string or an array”. This question is standard in competitive examination syllabi for Regular Expressions.

PHP 4.3 is the correct answer to “Parameter flags was added in which version of PHP”. This question is standard in competitive examination syllabi for Regular Expressions.