validation - w3toppers.com

A potentially dangerous Request.Form value was detected from the client

Which characters make a URL invalid?

In general URIs as defined by RFC 3986 (see Section 2: Characters) may contain any of the following 84 characters: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;= Note that this list doesn’t state where in the URI these characters may occur. Any other character needs to be encoded with the percent-encoding (%hh). Each part of the URI has further restrictions about … Read more

Validating input using java.util.Scanner [duplicate]

Overview of Scanner.hasNextXXX methods java.util.Scanner has many hasNextXXX methods that can be used to validate input. Here’s a brief overview of all of them: hasNext() – does it have any token at all? hasNextLine() – does it have another line of input? For Java primitives hasNextInt() – does it have a token that can be … Read more

How does the SQL injection from the “Bobby Tables” XKCD comic work?

It drops the students table. The original code in the school’s program probably looks something like q = “INSERT INTO Students VALUES (‘” + FNMName.Text + “‘, ‘” + LName.Text + “‘)”; This is the naive way to add text input into a query, and is very bad, as you will see. After the values … Read more

How can I validate an email address using a regular expression?

What’s the best way to validate an email address in JavaScript?

My form’s validate() is not working

You should use document.getElementsByName if you want to fetch the value using name attribute. I would recommend to do it by “id” attribute. function submitFunction() { var firstName = document.getElementsByName(“first_Name”)[0].value; if (firstName == “” || firstName == null || firstName.length == 0) { alert(“First Name is required”); return false; } } Also add return to … Read more

Specific String validation using regex

If you want to learn, how to use regex, I recommend the following read your lecture notes read a Java book (especially the chapters about “Pattern” and “regular expressions”) read the Java documentation, e.g. about Pattern

how to make a function that validates fields in a form? php [closed]

Here is a simple implementation – function validateUserName($uname){ $illegalCharacters = array(‘!’,’@’,’#’); // first check the length $length = strlen($uname); if ($length < 5 && $length > 10){ return false; }else{ // now check for illegal characters foreach($illegalCharacters AS $char){ if (strpos($uname,$char) != -1){ return false; } } } return true; } $userName = “user1905577”; if … Read more

phone number validation in js [closed]

I’d advise against stuff like this since there’s almost always a country where the phone numbers won’t match the validation, but here is the regex that matches your request ^\+?[0-9]{8,15}$