vue2 打印、导出

父组件

<template>
  <el-dialog :title="title" :visible.sync="open" width="1000px" append-to-body>
    <statement-preview :data-list="dataList" ref="statementPreview" @loadingChange="loadingChange" />
    <div slot="footer" class="dialog-footer print">
      <div>
        <el-progress v-show="printLoading" :percentage="exportPercentage"></el-progress>
      </div>
      <div>
        <el-button type="primary" :loading="printLoading" :disabled="printLoading" @click="onPrinter">打印</el-button>
        <el-button type="primary" :loading="printLoading" :disabled="printLoading" @click="onExportPDF">导出</el-button>
        <el-button @click="cancel">关 闭</el-button>
      </div>
    </div>
  </el-dialog>
</template>
<script>
import StatementPreview from "./StatementPreview.vue";
import { sortData } from "../utils";
import store from "@/store";
export default {
  name: "StatementSelectView",
  components: { StatementPreview },
  data() {
    return {
      title: "导出/打印 预览效果",
      open: false,
      dataList: [],
      printLoading: false,
      exportPercentage: 0, // 初始进度值
      status: "active" // 进度条状态
    };
  },
  created() {},
  mounted() {},
  methods: {
    init(dataList) {
      this.dataList = sortData(dataList);
      this.open = true;
    },

    // 打印
    onPrinter() {
      this.$refs.statementPreview.printer();
    },
    // 导出
    onExportPDF() {
      this.$refs.statementPreview.exportPDF();
    },
    loadingChange(value) {
      const { exportPercentage, printLoading } = value;
      this.printLoading = printLoading;
      this.exportPercentage = Number(exportPercentage) > 100 ? 100 : Number(exportPercentage);
    },
    // 取消按钮
    cancel() {
      this.open = false;
    }
  }
};
</script>
<style lang="scss" scoped>
  .print {
    display: flex;
    align-items: center;
    justify-content: space-between;

    ::v-deep {
      .el-progress-bar {
        width: 300px !important;
      }

      .el-progress-bar__outer {
        height: 15px !important;
      }

      .el-progress-bar__inner {
        background-color: #409eff;
        background-image: -webkit-linear-gradient(
          45deg,
          rgba(255, 255, 255, 0.15) 25%,
          transparent 25%,
          transparent 50%,
          rgba(255, 255, 255, 0.15) 50%,
          rgba(255, 255, 255, 0.15) 75%,
          transparent 75%,
          transparent
        );
        background-image: -o-linear-gradient(
          45deg,
          rgba(255, 255, 255, 0.15) 25%,
          transparent 25%,
          transparent 50%,
          rgba(255, 255, 255, 0.15) 50%,
          rgba(255, 255, 255, 0.15) 75%,
          transparent 75%,
          transparent
        );
        background-image: linear-gradient(
          45deg,
          rgba(255, 255, 255, 0.15) 25%,
          transparent 25%,
          transparent 50%,
          rgba(255, 255, 255, 0.15) 50%,
          rgba(255, 255, 255, 0.15) 75%,
          transparent 75%,
          transparent
        );
        -webkit-background-size: 1rem 1rem;
        background-size: 1rem 1rem;
        animation: 2s linear infinite pbs;
        animation-iteration-count: 10;
      }

      @keyframes pbs {
        0% {
          background-position-x: 1rem;
        }
      }
    }
  }
</style>

子组件

<template>
  <div :class="['print-box', { 'pdf': isPdf }]">
    <div v-for="(item, index) in dataList" :key="index">
      <!-- 需要打印的内容-->
      
    </div>
  </div>
</template>
<script>
import html2canvas from "html2canvas";
import jsPDF from "jspdf";
export default {
  name: "StatementPreview",
  props: {
    dataList: {
      type: Array,
      default: [],
      required: true
    }
  },
  components: {
  },
  data() {
    return {
      isPdf: false,
      exportPercentage: 0,
      printLoading: false,
      exportLoading: false
    };
  },
  created() {},
  mounted() {},
  methods: {
    printer() {
      this.printLoading = true;
      this.isPdf = true;
      this.loadingChange();
      let dom = document.querySelector(".print-box");
      let time = setTimeout(() => {
        this.generatePrint(dom).then(() => {
          this.isPdf = false;
          this.printLoading = false;
          this.loadingChange();
        });
        clearTimeout(time);
        time = null;
      }, 100);
    },
    generatePrint(dom) {
      return new Promise((resolve, reject) => {
        let reportItem = dom.querySelectorAll(".report-dom");
        const pageNumber = Math.floor((100 / reportItem.length) * 10) / 10;
        let nextData = null;
        if (pageNumber > 0) nextData = reportItem.entries();
        let div = document.createElement("div");
        const printPage = (value) => {
          // 生成打印的图片
          if (value.done) {
            // 结束
            console.log(div);
            this.$print(div);
            // document.body.appendChild(div);
            this.exportPercentage = 0;
            resolve();
          } else {
            html2canvas(value.value[1], {
              scale: 2,
              backgroundColor: "#ffffff",
              useCORS: true,
              scrollY: 0,
              scrollX: 0
              // width: 794,
              // height: 1123
            }).then((canvas) => {
              const imgData = canvas.toDataURL("image/jpeg", 1.0);
              let img = document.createElement("img");
              img.classList.add("printImg");
              img.src = imgData;
              div.appendChild(img);
              // // 进度条
              if (this.exportPercentage >= 100) this.exportPercentage = 100;
              else {
                let value = this.exportPercentage + pageNumber;
                value = Math.round(value, 1);
                this.exportPercentage = value;
              }
              this.loadingChange();
              printPage(nextData.next());
            });
          }
        };
        if (nextData) printPage(nextData.next());
        else this.$message.warning("打印异常，请稍后重试");
      });
    },
    exportPDF() {
      this.exportLoading = true;
      this.isPdf = true;
      this.loadingChange();
      let dom = document.querySelector(".print-box");
      let time = setTimeout(() => {
        this.generatePDF(dom).then(() => {
          this.isPdf = false;
          this.exportLoading = false;
          this.loadingChange();
        });
        clearTimeout(time);
        time = null;
      }, 300);
    },
    generatePDF(dom) {
      return new Promise((resolve, reject) => {
        let reportItem = dom.querySelectorAll(".report-dom");
        const pageNumber = Math.floor((100 / reportItem.length) * 10) / 10;
        const pdf = new jsPDF("", "pt", "a4");
        let nextData = null;
        if (pageNumber > 0) nextData = reportItem.entries();
        const pdfPage = (value) => {
          if (value.done) {
            // 结束
            pdf.save(`导出.pdf`);
            this.exportPercentage = 0;
            resolve();
          } else {
            html2canvas(value.value[1], {
              scale: 2,
              backgroundColor: "#ffffff",
              scrollY: 0,
              scrollX: 0,
              width: 794,
              height: 1123,
              useCORS: true // 是否尝试使用CORS从服务器加载图像 (allowTaint 允许跨域 不允许同时true)
            }).then((canvas) => {
              const contentWidth = canvas.width;
              const contentHeight = canvas.height;
              const imgWidth = 595.28;
              const imgHeight = (595.28 / contentWidth) * contentHeight;
              const pageData = canvas.toDataURL("image/jpeg", 1.0);
              pdf.addImage(pageData, "JPEG", 0, 0, imgWidth, imgHeight);
              if (value.value[0] !== reportItem.length - 1) pdf.addPage();
              // 导出进度条
              if (this.exportPercentage >= 100) this.exportPercentage = 100;
              else {
                let value = this.exportPercentage + pageNumber;
                value = Math.round(value, 1);
                this.exportPercentage = value;
              }
              this.loadingChange();
              // end
              pdfPage(nextData.next());
            });
          }
        };
        if (nextData) pdfPage(nextData.next());
        else this.$message.warning("导出异常，请稍后重试");
      });
    },
    // 改变父组件的loading状态
    loadingChange() {
      this.$emit("loadingChange", { exportPercentage: this.exportPercentage, printLoading: this.printLoading || this.exportLoading });
    }
  }
};
</script>
<style lang="scss" scoped>
  .pdf {
    .report-dom {
    }
  }
</style>

print.js

// 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>";
        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')
                        }
                    }
                }
            }
          }
        // 包裹要打印的元素
        // fix: https://github.com/xyl66/vuePlugs_printjs/issues/36
        let outerHTML = this.dom.innerHTML;
        return outerHTML;
    },
    // 向父级元素循环，包裹当前需要打印的元素
    // 防止根级别开头的 css 选择器不生效
    wrapperRefDom: function (refDom) {
        let prevDom = null
        let currDom = refDom
        // 判断当前元素是否在 body 中，不在文档中则直接返回该节点
        if (!this.isInBody(currDom)) return currDom
        while (currDom) {
            if (prevDom) {
                let element = currDom.cloneNode(false)
                element.appendChild(prevDom)
                prevDom = element
            } else {
                prevDom = currDom.cloneNode(true)
            }
            currDom = currDom.parentElement
        }
    
        return prevDom
    },
    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);
        }
    },
    // 检查一个元素是否是 body 元素的后代元素且非 body 元素本身
    isInBody: function (node) {
          return (node === document.body) ? false : document.body.contains(node);
    },
    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 PrintPlugin = {};
PrintPlugin.install = function(Vue, options) {
    Vue.prototype.$print = Print;
};
export default PrintPlugin;