Often the data type of a variable constrains what you can do with it. For example, you can't perform array-related functions on simple strings. Similarly, you may want to make sure that a variable contains an integer or a float before using it in a mathematical calculation, even though PHP will often help you by changing types for you in this situation.
opendir() function
readdir()
Q: – What function do you use to read a line of data from a file?
fgets()
feof()
Your goal should always be to make your code easy to read and understand. A variable such as $ab123245 tells you nothing about its role in your script and invites typos. Keep your variable names short and descriptive. A variable named $f is unlikely to mean much to you when you return to your code after a month or so. A variable named $filename, on the other hand, should make more sense.
Q: – What function do you use to write a line of data to a file?
fputs() function
popen()
$a_value_submitted_by_a_user
$666666xyz
$xyz666666
$_____counter_____
$the first
$file-name
The variable name $666666xyz is not valid because it does not begin with a letter or an underscore character
Submitted By:-Payal Gupta Email-ID: – payalgupta1325@yahool.com
