It's important to take security seriously when building web applications, especially when it comes to getting data from users.
As a general security rule, don't trust anyone, so you can't expect users to always enter the correct values into forms. For example, instead of entering the correct email address in the field, the user can enter the wrong address, or even some malicious data.
When it comes to validating user data, it can be done both on the client side (in a web browser) and on the server side.
Previously, client-side validation could only be done using JavaScript. But things have changed (or almost changed) because with HTML5, validation can be done in the browser, without the need to write complex JavaScript validation scripts.
Form Validation with HTML5HTML5 provides a fairly robust mechanism based on the following tag attributes: type , pattern , and require . With these new attributes, you can outsource some of the data validation to the browser.
Let's take a look at these attributes to see how they can help with form validation.
type attributeThis attribute tells which input field to display for data processing, for example, the already familiar field of type
Some input fields already provide standard validation methods without the need to write additional code. For example, it checks a field to ensure that the entered value matches the pattern of a valid email address. If an invalid character is entered in a field, the form cannot be submitted until the value is corrected.
Try playing around with the email field values in the demo below.
There are also other standard field types, like , and for validating numbers, URLs, and phone numbers, respectively.
Note: The phone number format varies from country to country due to the inconsistency in the number of digits in phone numbers and format differences. As a result, the specification does not define an algorithm for checking phone numbers, so at the time of writing this feature is poorly supported by browsers.
Luckily for us, phone number validation can be done using the pattern attribute, which takes a regular expression as an argument, which we'll look at next.
pattern attributeThe pattern attribute is likely to make many front-end developers jump for joy. This attribute accepts a regular expression (similar to the JavaScript regular expression format) against which the correctness of the data entered in the field will be checked.
Regular expressions are a language used to parse and manipulate text. They are often used for complex search and replace operations and for validating entered data.
Today, regular expressions are included in most popular programming languages, as well as in many scripting languages, editors, applications, databases, and command line utilities.
Regular expressions (RegEX) are a powerful, concise, and flexible tool for matching a string of text, such as single characters, words, or character patterns.
By passing a regular expression as the value of the pattern attribute, you can specify which values are acceptable for a given input field, as well as informing the user about errors.
Let's look at a couple of examples of using regular expressions to validate the value of input fields.
Phone numbersAs mentioned earlier, the tel field type is not fully supported by browsers due to inconsistencies in phone number formats in different countries.
For example, in some countries the phone number format is xxxx-xxx-xxxx , and the phone number itself will be something like this: 0803-555-8205 .
The regular expression that this pattern matches is: ^\d(4)-\d(3)-\d(4)$ . In code, this can be written like this:
phone number:
Alphanumeric values The required attributeThis is a boolean attribute used to indicate that the value of this field is required in order to submit the form. When adding this attribute to a field, the browser will require the user to complete the field before submitting the form.
This saves us from having to implement field validation with JavaScript, which can save developers some time.
For example: or (for XHTML compatibility)
All the demos you've seen above use the required attribute, so you can try it out by trying to submit the form without filling in the fields.
ConclusionBrowser support for form validation is pretty good, and for older browsers you can use polyfills.
It's worth noting that relying only on browser-side validation is dangerous, as these validations can be easily bypassed by attackers or bots.
Not all browsers support HTML5, and not all data sent to your script will come from your form. This means that before finally accepting data from the user, it is necessary to check their correctness on the server side.
For any web developer, there is no more serious problem yet than the complete cross-browser compatibility of his product. This is probably one of the main tasks of a good specialist: to ensure that his site always displays correctly in all browsers.
The required parameter, which is sometimes used for input, doesn't work in ancient IE, so it just can't be left that way. Retiree users who still use IE6 should have the same ease of use as users of the latest version of Google Chrome. Who, other than web developers, can take care of them.
About sore, about Internet ExplorerFor normal browsers, which include Firefox, Opera and Google Chrome, this task is relatively easy. Even old versions of these browsers display html code equally well, unless, of course, some new technologies are used in it. But to achieve this in the browsers of the Internet Explorer family, a titanic effort is required.
Each version of Internet Explorer has its own unique stupidity. What works in IE6 may not work properly in IE7 and vice versa. This zoo company Microsoft could not overcome even in the latest version of its browser.
I can’t understand why browser developers can’t just take it open and read the W3C standards for site building.
Therefore, as a web developer, I have to act as a kind of “layer” between capricious browsers and site visitors who require knowledge and spectacle. And it's great that web developers are succeeding so far.
So how do you get required to work in older versions of IE?JS comes to the rescue. I used to hate it, but now I don’t see a way forward without it in the space of the “correct” WEB.
I did not invent the solution below myself, but took it from a bourgeois blog. Since I am greedy, and the blog is bourgeois, I will not link to it.
The fnCheckFields() function will be responsible for everything. Place the JS code on your site:
function fnCheckFields(form_obj)( var error_msg = "Please complete all required fields."; var is_error = false; for (var i = 0; form_obj_elem = form_obj.elements[i]; i++) if (form_obj_elem.type "input" || form_obj_elem.type "text") if (form_obj_elem.getAttribute("required") && !form_obj_elem.value) is_error = true; if (is_error) alert(error_msg); return !is_error; )
It is generally recommended to place it between the html HEAD tags at the top of the page, but I would still recommend placing it at the very bottom of the page before the closing BODY tag. Thus, JS has less impact on page loading speed.
The input window, where the required parameter should be entered, should look like this in html language:
This script works very simply: after clicking the Submit button, the script checks all inputs for the presence of the required parameter and, if it finds it, then looks at the entered value of this field accordingly. If nothing is entered in such an input, then a warning window is displayed about the need for input. The data is not sent anywhere.
It is also great that if you have a normal browser that has already learned to understand this parameter as expected, such a warning window will not pop up and the standard tools for processing the required parameter for your browser will work.
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Hey guys hope things are going well, today we will be explaining a very useful tutorial along with you. In today's tutorial, we will create a simple contact form using angularJS and php.
The contact form is a standard web page that is available on every site. This allows site visitors to contact site owners or service providers who are responsible for maintaining this website. So we think why not create a simple contact form using Angularjs and php to receive messages from websites, readers and/or users.
We are using Angularjs for the front end and php on the server side. We will be writing a php code that takes data from an Angular form and emails it to the site administrator. Create a folder named "contact-form" in your application web directory and create a sample HTML page design - index.html. Now copy and paste the code below into your index.html file.
Demo - Simple contact form with Angularjs and php Contact form with angularjs and PHP Your name Mail Message Submit
php code to send emailCreate a contact.php page and copy paste the code below. Following is the php code that will fetch data from an angular form and send it via email, to the given email address.
< ?php $post_data = file_get_contents("php://input"); $data = json_decode($post_data); //Just to display the form values echo "Name: " . $data->name; echo "Email: " . $data->email; echo "Message: " . $data->message; // sned an email $to = $data->email; $subject = "Test email site for testing angularjs contact form"; $message = $data->message; $headers = "From: " . $data->name .. "\r\n" .. "\r\n" . "XMailer: PHP/" . phpversion(); // PHP mail function to send email to an email address mail($to, $subject, $message, $headers); ?>
Instructions: Here is a table with 49 numbers - 25 in small print and 24 in large print. You need to look for numbers in small print from 1 to 25 in ascending order, and in large print from 24 to 1 in descending order. This must be done in turn: 1 - in small print, 24 - in large print, 2 - in small print, 23 - in large print, etc. When you find the number, write it down on the control sheet along with the letter next to it.
Task completion time - 5 min.
|
7th |
4-in |
15-in |
8-hour |
11-to |
1-g |
25th |
|
14th |
18-l |
21-f |
15th |
3rd |
19th |
17-z |
|
7th |
2nd |
11-t |
10-s |
23rd |
8th |
10-a |
|
17-b |
14-p |
6-r |
20-p |
13h |
23rd |
5th |
|
9th |
3-l |
22-b |
1st |
16th |
6-d |
13th |
|
2nd |
4th |
22-0 |
20th |
12th |
19-z |
24th |
|
24th |
18-s |
12-t |
9-to |
16-n |
21-d |
5th |
Control form:
|
Coarse shr. |
Results: . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evaluation of results (distribution and switching of attention):
Method "Reproduction of geometric shapes" (middle and older adolescence) Instruction. For 10 seconds, it is proposed to carefully consider the figures inscribed in square 10 ... Method "Find a mistake in proverbs" Instructions: Find the mistake in the proverbs. The time to complete the task is 3 minutes. On the form... Methodology "assessment of operational visual memory" The working visual memory of a child and its indicators can be determined using the following ...
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