The reason for the error is NameResolutionError(self.host,self,e)frome, which is an exception type in the urllib3 library. The reason for this error is that DNS resolution failed, that is, the host name or IP address attempted to be resolved cannot be found. This may be caused by the entered URL address being incorrect or the DNS server being temporarily unavailable. How to solve this error There may be several ways to solve this error: Check whether the entered URL address is correct and make sure it is accessible Make sure the DNS server is available, you can try using the "ping" command on the command line to test whether the DNS server is available Try accessing the website using the IP address instead of the hostname if behind a proxy

Differences: 1. Different definitions, url is a uniform resource locator, and html is a hypertext markup language; 2. There can be many urls in an html, but only one html page can exist in a url; 3. html refers to is a web page, and url refers to the website address.

How to reduce memory usage through PHP functions. In development, memory usage is a very important consideration. If a large amount of memory is used in a program, it may cause slowdowns or even program crashes. Therefore, reasonably managing and reducing memory usage is an issue that every PHP developer should pay attention to. This article will introduce some methods to reduce memory usage through PHP functions, and provide specific code examples for readers' reference. Use the unset() function to release variables in PHP. When a variable is no longer needed, use

How to optimize the lazy loading effect of images through PHP functions? With the development of the Internet, the number of images in web pages is increasing, which puts pressure on page loading speed. In order to improve user experience and reduce loading time, we can use image lazy loading technology. Lazy loading of images can delay the loading of images. Images are only loaded when the user scrolls to the visible area, which can reduce the loading time of the page and improve the user experience. When writing PHP web pages, we can optimize the lazy loading effect of images by writing some functions. Details below

The performance of different PHP functions is crucial to application efficiency. Functions with better performance include echo and print, while functions such as str_replace, array_merge, and file_get_contents have slower performance. For example, the str_replace function is used to replace strings and has moderate performance, while the sprintf function is used to format strings. Performance analysis shows that it only takes 0.05 milliseconds to execute one example, proving that the function performs well. Therefore, using functions wisely can lead to faster and more efficient applications.

PHP image processing functions are a set of functions specifically used to process and edit images. They provide developers with rich image processing functions. Through these functions, developers can implement operations such as cropping, scaling, rotating, and adding watermarks to images to meet different image processing needs. First, I will introduce how to use PHP image processing functions to achieve image cropping function. PHP provides the imagecrop() function, which can be used to crop images. By passing the coordinates and size of the cropping area, we can crop the image

PHP function introduction: strtr() function In PHP programming, the strtr() function is a very useful string replacement function. It is used to replace specified characters or strings in a string with other characters or strings. This article will introduce the usage of strtr() function and give some specific code examples. The basic syntax of the strtr() function is as follows: strtr(string$str, array$replace) where $str is the original word to be replaced.

PHP functions have similarities with functions in other languages, but also have some unique features. Syntactically, PHP functions are declared with function, JavaScript is declared with function, and Python is declared with def. In terms of parameters and return values, PHP functions accept parameters and return a value. JavaScript and Python also have similar functions, but the syntax is different. In terms of scope, functions in PHP, JavaScript and Python all have global or local scope. Global functions can be accessed from anywhere, and local functions can only be accessed within their declaration scope.