Php Filter MCQs with Explanations

There are two main types of filtering: validation and sanitization.

filter_var() – Filters a single variable with a specified filter.

Option a) describes Sanitizing filters.

Since the integer is “300” it is not in the specified range, and the output of the code above will be: “Integer is not valid”.

There is an undocumented filter flag for FILTER_VALIDATE_BOOLEAN. The documentation implies that it will return NULL if the value doesn’t match the allowed true/false values. However this doesn’t happen unless you give it the FILTER_NULL_ON_FAILURE flag.

The code above converts all “_” to white spaces. Call the filter_var() function with the FILTER_CALLBACK filter and an array containing our function.

All of the mentioned is the correct answer to “Which of the following is/are an external data? 1. Cookies 2. Input data from a form 3. Server Variables 4. Web services data”. This question is standard in competitive examination syllabi for Php Filter.

filter_var_array() is the correct answer to “Which one of the following filter is used to filter several variables with the same or different filters”. This question is standard in competitive examination syllabi for Php Filter.

filter_has_var is the correct answer to “Which one of the following filter checks if variable of specified type exists”. This question is standard in competitive examination syllabi for Php Filter.