Phpin_array, trim, isset, unset, is_numeric function usage. -PHP source code

Phpin_array, trim, isset, unset, is_numeric function usage. Php in_array, trim, isset, unset, is_numeric function usage.

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Next, let's take a look at the tutorials on using these functions.

In_array ($ array)

This function is used to determine whether the current value is an array.

EX:

$ Array = array (1, 2 );
If (in_array ($ array ))
{
Die ('in _ array determines it is an array ');
}
Echo 'not an array ';

Result:

In_array determines it is an array

Trim ($ value)

The trim function removes the null values of parameters, including null ,""

Isset ($ value)

Isset is used to determine whether a variable exists.

Unset ($ value)

Destroy variable

Let's take a look at isset and unset instances.

$ A = 'V ';

Isset ($ )? $ A: NULL;

Unset ($ );

Isset ($ )? $ A: NULL;

The result is:

V

Null

Is_numeric ($ num)

$ Num = 3;

If (is_numeric ($ num ))
{
Echo $ num;
}
Else
{
Echo 'not a numerical value ';
}

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