isset() Function in PHP

The isset() function of PHP usually checks whether variable is set/declared and it is different/other than the NULL. If the variable is unset using the unset() function in PHP then it is no need to be considered at all to set. The isset() function will return the value TRUE only if the variable existed which is not NULL. Otherwise isset() function will return the value FALSE value when the function will check the variable which is assigned to the NULL term. NULL character “

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