Article Introduction：php random verification code php generates random verification code (graphic and text)

2016-07-25 comment 0  1236

Article Introduction：Detailed explanation of php random verification code image generation example

2016-07-25 comment 0  1056

Article Introduction：Detailed explanation of how PHP randomly generates image verification codes

2016-07-25 comment 0  961

Article Introduction：PHP realizes the generation and verification of image verification codes. In website development, in order to prevent malicious machine attacks or automatic registration, we often use image verification codes for verification. This article will introduce how to use PHP to generate and verify image verification codes, and give specific code examples. Generating an image verification code The key to generating an image verification code is to generate a random verification code string and draw it onto the image. The following is a sample code that generates an image verification code: <?phpsession_start();//

2023-09-13 comment 0  942

Article Introduction：PHP: Use the gd library to generate images and implement random verification codes

2016-10-10 comment 0  1214

Article Introduction：Tips for generating random verification code images using PHP and GD libraries. Random verification code images are a common security verification mechanism in website development. It requires users to enter the correct verification code to continue the operation. In this article, we will introduce techniques on how to generate random verification code images using PHP and the GD library. The GD library is an open source library for processing images, which provides PHP with rich image processing functions. By using the GD library, we can easily generate various verification code images. First, we need to create a PHP file named

2023-07-14 comment 0  969

Article Introduction：Use PHP's GD library to generate a picture with a verification code and save the verification code in the Session. You can use the rang() function to generate random verification codes; use the imagecolorallocate() method to assign colors to images; use ajax to refresh and generate new verification codes when you click on the verification code.

2019-09-29 comment 0  4514

Article Introduction：How to generate a verification code using PHP Image verification code (CAPTCHA) is a common technique used to authenticate users or restrict access to automated programs. By generating random images and requiring users to identify the correct characters or images, CAPTCHAs can effectively prevent bot attacks and spam registrations. In this article, we will introduce how to use PHP to generate a verification code image and display it on the page. First, we need to create a PHP file to generate the verification code image. You can name it captcha.php and make sure

2023-08-19 comment 0  1941

Article Introduction：PHP study notes: Use the gd library to generate images and implement random verification codes

2016-09-14 comment 0  961

Article Introduction：Library management system source code: Library management system source code php Generate random verification code image code: Copy the code as follows: <?php /** Default homepage**/ class DefaultController extends AppController { public function index() { $len = 5 ; $str = "ABCDEFGHIJKLNMPQRSTUVWXYZ123456789"; $im = imagecreatetruecolor ( 70, 20 );

2016-07-29 comment 0  1852

Article Introduction：PHP verification code PHP non-preset image generates verification code

2016-07-25 comment 0  1115

Article Introduction：How to generate verification code image after saving remote image in PHP? With the development of the Internet, verification codes have become one of the important means of website security. CAPTCHA is an image or text-based verification mechanism that is often used to identify whether a user is a human or a machine. In some cases, we need to download an image from a remote server and display it as a captcha (verification code) image. This article will introduce how to use PHP to save remote images and generate verification code images. First, we need to use PHP

2023-07-12 comment 0  914

Article Introduction：How to use PHP arrays to generate dynamic images and verification codes. With the development of the Internet, verification codes (CAPTCHA) are widely used in various websites and applications to verify the authenticity of users and prevent malicious attacks from automated programs. Using PHP arrays to generate dynamic images and verification codes is a common and effective method. This article will introduce how to use PHP arrays to generate dynamic images and verification codes to ensure the security of the website. Generate a random verification code First, we need to generate a random verification code. We can use PHP

2023-07-16 comment 0  1531

Article Introduction：This article mainly uses the GD library to put random strings on images to generate verification codes, thereby interfering with computer recognition.

2021-03-17 comment 0  2884

Article Introduction：How to use PHP to generate refreshable image verification codes. With the development of the Internet, in order to prevent malicious attacks and automatic machine operations, many websites use verification codes for user verification. One common type of verification code is the image verification code, which generates a picture containing random characters and requires the user to enter the correct characters before proceeding. This article will introduce how to use PHP to generate refreshable image verification codes and provide specific code examples. Step 1: Create a verification code image First, we need to create a verification code image

2023-09-13 comment 0  1098

Article Introduction：How to use PHP to generate responsive verification code images With the rapid development of the Internet, people are paying more and more attention to information security. In order to prevent malicious attackers from performing malicious operations through automated scripts, websites often use verification codes as a means to verify the authenticity of users. CAPTCHA image is a common form of CAPTCHA that generates random images and numeric characters, requiring users to enter based on the characters on the image to verify their identity. This article will introduce how to use PHP to generate responsive verification code images and provide specific instructions.

2023-09-13 comment 0  709

Article Introduction：Detailed steps for generating verification code images using PHP and GD libraries Verification codes are a commonly used security verification mechanism that can be used to prevent malicious programs or robot automation. Automated attacks can be effectively prevented by generating a random image that requires users to enter the verification code shown in the image when logging in or registering. In this article, we will introduce in detail how to use PHP and GD library to generate verification code images. Step 1: Install and configure the GD library First, make sure your PHP environment has the GD library installed. If not installed

2023-07-13 comment 0  1103

Article Introduction：Generate verification code to randomly interfere with PHP implementation

2016-07-25 comment 0  987

Article Introduction：PHP generates alphanumeric verification code images

2016-07-25 comment 0  1011

Article Introduction：How to use PHP to generate a customizable style verification code. Image verification code is a technical means used to prevent malicious access or registration by robots. By generating verification codes that are difficult to recognize by machines, the security of the website can be effectively improved. This article will introduce how to use PHP to generate customizable style verification code images and provide specific code examples. First, we need to clarify the basic requirements of the verification code. Generally speaking, the verification code should contain some random letters and numbers, and have a certain distortion effect to increase the difficulty of machine recognition. at the same time,

2023-09-13 comment 0  746