在HTML5之前，有一系列jQuery的技术和插件来实现AJAX文件上传。HTML5引入了可以简化文件上传的FormData类。本篇文章给大家介绍一下使用jQuery HTML5和FormData上传文件的方法示例。$(#myform).on(sumbit, function(){var form = $(this);var formdata = false;if (window.FormData){formdata = new FormData(form[0]);}var formAction = form.attr(action);$.ajax({url : /upload,data : formdata ? formdata : for...
第一种方法代码实现的一种方法<!DOCTYPE html> <html lang="en"> <head><meta charset="UTF-8"><title>使用桃心形方程绘制爱心</title> </head> <body><canvas></canvas><script>var canvas = document.querySelector(canvas);var ctx = canvas.getContext(2d);canvas.width = window.innerWidth;canvas.height = window.innerHeight;var Heart = function(x, y) {this.x = x;this.y = y;this.vertices = [];for(let i=0; i<30; i+...
viewport 语法介绍： 代码如下:content=”height = [pixel_value | device-height] ,width = [pixel_value | device-width ] ,initial-scale = float_value ,minimum-scale = float_value ,maximum-scale = float_value ,user-scalable = [yes | no] ,target-densitydpi = [dpi_value | device-dpi | high-dpi | medium-dpi | low-dpi]”/> 参数解释： width—-控制 viewport 的大小，可以指定的一个值或者特殊的值，如 device-wid...