原生js获取上传文件路径并显示到img

function getObjectURL(file) {
		var url = null;
		if (window.createObjectURL != undefined) { // basic
			url = window.createObjectURL(file);
		} else if (window.URL != undefined) { // mozilla(firefox)
			url = window.URL.createObjectURL(file);
		} else if (window.webkitURL != undefined) { // webkit or chrome
			url = window.webkitURL.createObjectURL(file);
		}
		return url;
	}