Check if a string is true.

[hoangthi]

I have a form that only accepts the string: Axxxxxxx (x is a number)

EX: A1234567, A3145321

 

So, How can I check if the input is valid ?

 

If user input:

A1234567: True

B1234567: False

AA123121: False

A11 31231: False

 

Please help me!

[.josh]

// 1 or more numbers following

if ( preg_match('~^A[0-9]+$~',$string) ) {

  // true

}


// 2 or more numbers following

if ( preg_match('~^A[0-9]{2,}$~',$string) ) {

  // true

}


// exactly 7 numbers following

if ( preg_match('~^A[0-9]{7}$~',$string) ) {

  // true

}


// between 5 and 7 numbers following

if ( preg_match('~^A[0-9]{5,7}$~',$string) ) {

  // true

}

[hoangthi]

Thanks you so much! Admin