[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Z] validation client-side versus server-side client-side with JavaScript advantages debugging DOM 2nd events example script examples functions generic validation function JavaScript syntax loops and conditionals methods and properties navigator object objects common approaches effective models error reporting and ineffective models informative error messages post-validation models rekeying of data, avoiding server-side with PHP credit cards dates and times mandatory data numbers PEAR Date package, using strings time validation sessions and var_dump( ) function (PHP) array values, displaying with variable substitution variables 2nd destroying escape sequences and global variables passing to functions assigning by reference by reference default parameter values static variables types checking testing, setting, and unsetting variable assignment variable scope views |