1.首先安装
import html2canvas from 'html2canvas';
import { jsPDF } from 'jspdf';
2.引入打印插件print.js
import Print from "@/assets/js/print";
Vue.use(Print)
// 打印类属性、方法定义
/* eslint-disable */
const Print = function (dom, options) {
if (!(this instanceof Print)) return new Print(dom, options);
this.options = this.extend({
'noPrint': '.no-print'
}, options);
if ((typeof dom) === "string") {
this.dom = document.querySelector(dom);
} else {
this.isDOM(dom)
this.dom = this.isDOM(dom) ? dom : dom.$el;
}
this.init();
};
Print.prototype = {
init: function () {
var content = this.getStyle() + this.getHtml();
this.writeIframe(content);
},
extend: function (obj, obj2) {
for (var k in obj2) {
obj[k] = obj2[k];
}
return obj;
},
getStyle: function () {
var str = "",
styles = document.querySelectorAll('style,link');
for (var i = 0; i < styles.length; i++) {
str += styles[i].outerHTML;
}
str += "<style>" + (this.options.noPrint ? this.options.noPrint : '.no-print') + "{display:none;}</style>";
// str += "<style>html,body,div{height: auto!important;font-size:14px}</style>";
return str;
},
getHtml: function () {
var inputs = document.querySelectorAll('input');
var textareas = document.querySelectorAll('textarea');
var selects = document.querySelectorAll('select');
for (var k = 0; k < inputs.length; k++) {
if (inputs[k].type == "checkbox" || inputs[k].type == "radio") {
if (inputs[k].checked == true) {
inputs[k].setAttribute('checked', "checked")
} else {
inputs[k].removeAttribute('checked')
}
} else if (inputs[k].type == "text") {
inputs[k].setAttribute('value', inputs[k].value)
} else {
inputs[k].setAttribute('value', inputs[k].value)
}
}
for (var k2 = 0; k2 < textareas.length; k2++) {
if (textareas[k2].type == 'textarea') {
textareas[k2].innerHTML = textareas[k2].value
}
}
for (var k3 = 0; k3 < selects.length; k3++) {
if (selects[k3].type == 'select-one') {
var child = selects[k3].children;
for (var i in child) {
if (child[i].tagName == 'OPTION') {
if (child[i].selected == true) {
child[i].setAttribute('selected', "selected")
} else {
child[i].removeAttribute('selected')
}
}
}
}
}
return this.dom.outerHTML;
},
writeIframe: function (content) {
var w, doc, iframe = document.createElement('iframe'),
f = document.body.appendChild(iframe);
iframe.id = "myIframe";
//iframe.style = "position:absolute;width:0;height:0;top:-10px;left:-10px;";
iframe.setAttribute('style', 'position:absolute;width:0;height:0;top:-10px;left:-10px;');
w = f.contentWindow || f.contentDocument;
doc = f.contentDocument || f.contentWindow.document;
doc.open();
doc.write(content);
doc.close();
var _this = this
iframe.onload = function () {
_this.toPrint(w);
setTimeout(function () {
document.body.removeChild(iframe)
}, 100)
}
},
toPrint: function (frameWindow) {
try {
setTimeout(function () {
frameWindow.focus();
try {
if (!frameWindow.document.execCommand('print', false, null)) {
frameWindow.print();
}
} catch (e) {
frameWindow.print();
}
frameWindow.close();
}, 10);
} catch (err) {
console.log('err', err);
}
},
isDOM: (typeof HTMLElement === 'object') ?
function (obj) {
return obj instanceof HTMLElement;
} :
function (obj) {
return obj && typeof obj === 'object' && obj.nodeType === 1 && typeof obj.nodeName === 'string';
}
};
const MyPlugin = {}
MyPlugin.install = function (Vue, options) {
// 4. 添加实例方法
Vue.prototype.$print = Print
}
export default MyPlugin3.执行函数
// loding等待
toLoding() {
this.loading = this.$loading({
lock: true,
text: 'Loading',
spinner: 'el-icon-loading',
background: 'rgba(0, 0, 0, 0.7)'
});
// 导出按钮显示状态
this.pdfIsShowData = false;
// 展开所有节点
let activeNames = [];
for (let i = 0; i < Object.keys(this.dataAll).length; i++) {
activeNames.push((i));
}
this.activeNames = activeNames;
// 展开所有子节点
if (this.$refs.collapse && this.$refs.collapse.length > 0) {
this.$refs.collapse.forEach((item, index) => {
item.activeNames = ['0'];
})
}
// 关闭滚动条
this.isMaxHeight = false;
},
// 打印试卷
printPaper() {
// 等待节点全部展开
this.toLoding();
setTimeout(() => {
this.$nextTick(() => {
this.$print(this.$refs.printContent);
setTimeout(() => {
this.loading.close();
this.pdfIsShowData = true;
}, 1000)
});
}, 2000)
},
// 导出试卷
exportPaper() {
// 等待节点全部展开
this.toLoding()
setTimeout(() => {
this.$nextTick(() => {
// 获取目标元素
const element = document.querySelector('.toPdf');
// 使用 html2canvas 捕获快照
html2canvas(element).then(canvas => {
// 将 canvas 转换为图片数据
const imgData = canvas.toDataURL('image/png');
// 创建一个 jsPDF 实例
const pdf = new jsPDF('p', 'mm', 'a4');
const imgWidth = 210; // A4纸宽
const pageHeight = 297; // A4纸高
let imgHeight = canvas.height * imgWidth / canvas.width;
let heightLeft = imgHeight;
// 添加图像到 PDF 第一页
let position = 0;
pdf.addImage(imgData, 'PNG', 0, position, imgWidth, imgHeight);
heightLeft -= pageHeight;
// 如果内容超过一页，则添加更多页
while (heightLeft >= 0) {
position = heightLeft - imgHeight;
pdf.addPage();
pdf.addImage(imgData, 'PNG', 0, position, imgWidth, imgHeight);
heightLeft -= pageHeight;
}
// 下载 PDF 文件
pdf.save(`${this.testName}.pdf`);
this.pdfIsShowData = true
this.loading.close();
this.$message({
message: '导出成功',
type: 'success'
});
// 关闭滚动条
this.isMaxHeight = false;
}).catch(error => console.error('Error capturing the snapshot:', error));
});
}, 2000)
},4.样式问题
打印时候把所有字体颜色改为黑色
.toPdf-black * {
color: #000 !important;
}
<div :class="{ 'toPdf': true, 'toPdf-black': !pdfIsShowData }" ref="printContent"
