当我在Facebook上,并已打开的控制台,我看到下面这个图片。他们怎么做到的?
就像萤火虫,您可以使用%c
款式控制台日志输出。看看我们如何能够实现Facebook的例子:
console.log("%cStop!", "color: red; font-family: sans-serif; font-size: 4.5em; font-weight: bolder; text-shadow: #000 1px 1px;");
由于它支持CSS属性,我们甚至可以在有“画”图像:
(function(url) {
// Create a new `Image` instance
var image = new Image();
image.onload = function() {
// Inside here we already have the dimensions of the loaded image
var style = [
// Hacky way of forcing image's viewport using `font-size` and `line-height`
'font-size: 1px;',
'line-height: ' + this.height + 'px;',
// Hacky way of forcing a middle/center anchor point for the image
'padding: ' + this.height * .5 + 'px ' + this.width * .5 + 'px;',
// Set image dimensions
'background-size: ' + this.width + 'px ' + this.height + 'px;',
// Set image URL
'background: url('+ url +');'
].join(' ');
// notice the space after %c
console.log('%c ', style);
};
// Actually loads the image
image.src = url;
})('https://i.cloudup.com/Zqeq2GhGjt-3000x3000.jpeg');