Relevant code to control image size in web pages_JavaScript

1. Drag with the mouse to change the size

２ , Use mouse scrolling to control picture size
３. Use code to control the size of the image tag
４. CSS control image size
1. css2 direct implementation: img{max-width: 500px;} (IE is not supported yet)
2. Expression implementation: img{width:expression(width>500?"500px":width);} (IE only)
3. Use js. Method: Use document.getElementsByTagName("IMG") to get all img elements Traverse the img element to determine its width and perform corresponding operations