vue3 前端实现pdf打印预览 printjs

1. 在utils建print.ts文件

   interface PrintFunction {
   extendOptions: Function;
   getStyle: Function;
   setDomHeight: Function;
   toPrint: Function;
   }

   const Print = function (dom, options?: object): PrintFunction {
   options = options || {};
   // @ts-expect-error
   if (!(this instanceof Print)) return new Print(dom, options);
   this.conf = {
   styleStr: “”,
   // Elements that need to dynamically get and set the height
   setDomHeightArr: [],
   // Callback before printing
   printBeforeFn: null,
   // Callback after printing
   printDoneCallBack: null
   };
   for (const key in this.conf) {
   // eslint-disable-next-line no-prototype-builtins
   if (key && options.hasOwnProperty(key)) {
   this.conf[key] = options[key];
   }
   }
   if (typeof dom === “string”) {
   this.dom = document.querySelector(dom);
   } else {
   this.dom = this.isDOM(dom) ? dom : dom.$el;
   }
   if (this.conf.setDomHeightArr && this.conf.setDomHeightArr.length) {
   this.setDomHeight(this.conf.setDomHeightArr);
   }
   this.init();
   };

   Print.prototype = {
   /**

   • init
     /
     init: function (): void {
     const content = this.getStyle() + this.getHtml();
     this.writeIframe(content);
     },
     /*
   • Configuration property extension
   • @param {Object} obj
   • @param {Object} obj2
     /
     extendOptions: function (obj, obj2: T): T {
     for (const k in obj2) {
     obj[k] = obj2[k];
     }
     return obj;
     },
     /*
     Copy all styles of the original page
     */
     getStyle: function (): string {
     let str = “”;
     const styles: NodeListOf = document.querySelectorAll(“style,link”);
     for (let i = 0; i < styles.length; i++) {
     str += styles[i].outerHTML;
     }
     str += <style>.no-print{display:none;}${this.conf.styleStr}</style>;
     return str;
     },
     // form assignment
     getHtml: function (): Element {
     const inputs = document.querySelectorAll(“input”);
     const selects = document.querySelectorAll(“select”);
     const textareas = document.querySelectorAll(“textarea”);
     const canvass = document.querySelectorAll(“canvas”);

   for (let 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 (let k2 = 0; k2 < textareas.length; k2++) {if (textareas[k2].type == "textarea") {textareas[k2].innerHTML = textareas[k2].value;}
   }for (let k3 = 0; k3 < selects.length; k3++) {if (selects[k3].type == "select-one") {const child = selects[k3].children;for (const i in child) {if (child[i].tagName == "OPTION") {if ((child[i] as any).selected == true) {child[i].setAttribute("selected", "selected");} else {child[i].removeAttribute("selected");}}}}
   }for (let k4 = 0; k4 < canvass.length; k4++) {const imageURL = canvass[k4].toDataURL("image/png");const img = document.createElement("img");img.src = imageURL;img.setAttribute("style", "max-width: 100%;");img.className = "isNeedRemove";canvass[k4].parentNode.insertBefore(img, canvass[k4].nextElementSibling);
   }return this.dom.outerHTML;
   

   },
   /**
   create iframe
   */
   writeIframe: function (content) {
   let w: Document | Window;
   let doc: Document;
   const iframe: HTMLIFrameElement = document.createElement(“iframe”);
   const f: HTMLIFrameElement = document.body.appendChild(iframe);
   iframe.id = “myIframe”;
   iframe.setAttribute(
   “style”,
   “position:absolute;width:0;height:0;top:-10px;left:-10px;”
   );
   // eslint-disable-next-line prefer-const
   w = f.contentWindow || f.contentDocument;
   // eslint-disable-next-line prefer-const
   doc = f.contentDocument || f.contentWindow.document;
   doc.open();
   doc.write(content);
   doc.close();

   const removes = document.querySelectorAll(".isNeedRemove");
   for (let k = 0; k < removes.length; k++) {removes[k].parentNode.removeChild(removes[k]);
   }// eslint-disable-next-line @typescript-eslint/no-this-alias
   const _this = this;
   iframe.onload = function (): void {// Before popping, callbackif (_this.conf.printBeforeFn) {_this.conf.printBeforeFn({ doc });}_this.toPrint(w);setTimeout(function () {document.body.removeChild(iframe);// After popup, callbackif (_this.conf.printDoneCallBack) {_this.conf.printDoneCallBack();}}, 100);
   };
   

   },
   /**
   Print
   /
   toPrint: function (frameWindow): void {
   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.error(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”
   );
   },
   /*

   • Set the height of the specified dom element by getting the existing height of the dom element and setting
   • @param {Array} arr
     */
     setDomHeight(arr) {
     if (arr && arr.length) {
     arr.forEach(name => {
     const domArr = document.querySelectorAll(name);
     console.log(name, domArr);
     domArr.forEach(dom => {
     dom.style.height = dom.offsetHeight + “px”;
     });
     });
     }
     }
     };

   export default Print;

2. .vue页面使用
   html

   <div class="w-full p-1" id="printApply" style="overflow: auto"><div class="text-center text-2xl">江苏微导纳米股份有限公司</div><div class="text-center text-xl mb-6 mt-2">工具出库单</div><div class="flex"><div class="flex-1 mb-2"><div class="mb-3">事业部：{{ dataSource.chargeDept }}</div><div class="mb-3">班组: {{ dataSource.groupName }}</div><div class="">联系人： ____________________</div></div><div class="flex-1 mb-2"><div class="mb-3">申请人：{{ dataSource.applicant }}</div><div class="mb-3">申请部门：{{ dataSource.applicantDept }}</div><div class="">联系电话： _____________________</div></div><div class="flex-1 mb-2"><div class="mb-3">工具属性：{{ dataSource.toolProperty }}</div><div class="mb-3">工厂: {{ dataSource.factoryName }}</div></div></div><div class="my-3 w-full"><table><colgroup><col width="50" /><col width="120" /><col width="150" /><col width="150" /><col width="100" /><col width="100" /><col width="100" /><col width="100" /></colgroup><tbody><tr height="32" class=""><td class="text-center font-bold">序号</td><td class="text-center font-bold">存货编码</td><td class="text-center font-bold">存货名称</td><td class="text-center font-bold">需求时间</td><td class="text-center font-bold">重要程度</td><td class="text-center font-bold">请购用途</td><td class="text-center font-bold">规格型号</td><!-- <td class="text-center font-bold">工具大类</td> --><td class="text-center font-bold">申领数量</td></tr><template v-for="(item, index) in dataSource.lists"><tr height="32"><td class="text-center">{{ index+1 }}</td><td class="text-center">{{ item.cInvCode }}</td><td class="text-center">{{ item.cInvName }}</td><td class="text-center">{{ item.demandTime&&item.demandTime.slice(0, 10) }}</td><td class="text-center">{{ item.significance }}</td><td class="text-center">{{ item.purpose }}</td><td class="text-center">{{ item.cInvStd }}</td><!-- <td class="text-center">{{ item.toolType }}</td> --><td class="text-center">{{ item.applicationQty }}</td></tr></template><tr height="32"><td class="text-center font-bold">合计：</td><td colspan="6" class="text-left"></td><td class="text-center">{{sum}}</td></tr><tr height="65"><td colspan="8" class="text-left ">备注：<br />1、请双方确认无误后签字确认，谢谢！</td></tr></tbody></table></div><div class="w-4/5 mt-2 flex justify-around"><div class=""><div class="">发起人签字:</div><div class="mt-2">发起日期:</div></div><div class=""><div class="">审批人签字:</div><div class="mt-2">审批日期:</div></div></div>
   </div>
   

css

#printApply {display: none;
}
// 设置打印的时候，显示
#printApply {@media print {display: block;}
}#printApply table {border-top: 1px solid #333;border-left: 1px solid #333;border-spacing: 0;background-color: #fff;width: 100%;
}
#printApply table td {border-bottom: 1px solid #333;border-right: 1px solid #333;font-size: 14px;padding: 5px;
}

ts

import {Printer
} from "@element-plus/icons-vue";
import Print from "@/utils/print";const dataSource = ref({chargeDept: "",groupName: "",applicant: "",applicantDept: "",toolProperty: "",factoryName: "",lists: []
})
let sum = 0
const handlePrint = async (row) => {sum = 0dataSource.value = rowdataSource.value.lists.forEach((item) => {sum += item.applicationQty})setTimeout(() => {Print("#printApply").toPrint;},500)
};

注意：在主页面打印 需要给#printApply设置隐藏 设置打印的时候，再显示，即

#printApply {display: none;
}
#printApply {@media print {display: block;}
}