最近帮同事解决一个前端页面布局问题，技术背景vue+elementui，出现问题如下：点击详情表格布局一切正常（列数不固定，估计后端返回决定）点击打印之后的表格出现不能撑满，多出空白列的情况。

 未点击打印时布局展示

 经过各种调试主要解决由：tableLayout属性用来显示表格单元格、行、列的算法规则

①auto：（默认值）列宽度由单元格内容设定；

 ②fixed: 列宽由表格宽度和列宽度设定；

 ③inherit：规定应该从父元素继承table-layout属性的值。

/设置表格布局算法*/
 table{
     table-layout:auto!important;
}

和重新给elementui的表格内的宽度一定要设置成100%,.el-table__header和.el-table__body这个是框架内置的一些样式，得css重新更改

.el-table__header{
  width: 100%!important;
}
.el-table__body{
  width: 100%!important;
}

附带让表格内容超过自适宽度就换行

word-wrap: normal!important;
width: auto!important;
word-break: break-all!important;

修改完成后打印的表格展示就正常了 

 其中打印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')
            }
          }
        }
      }
    }

    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 MyPlugin

print.css样式

@media print {

    section{
        margin-top: -35px;
    }
    .el-table__header{
      width: 100%!important;
    }
    .el-table__body{
      width: 100%!important;
    }
  .el-table__header{
    table-layout: auto;
    }
  .el-table__body{
    table-layout: auto!important;
  }

  .modal-body {
    min-height: auto;
  }

  .el-table--border th, .el-table--border td{
    border-right: 1px solid #ebeef5;
  }
  .el-table th, .el-table td{
    padding: 0px;
  }
  .el-table .cell{
    padding-right: 0px;
  }
  .el-table{
    width: 100%!important;
  }
}

具体vue页面部分关键代码

<template>
  <div id="associateInfo">
    <v-breadcrumb :title="vBreadCrumbData"></v-breadcrumb>
    <div class="pull-right">
      <span class="fa fa-print fa-2x" @click="printContent()" style="cursor: pointer"></span>
      <span>&nbsp</span>
    </div>
    <div style="margin-top: 10px;padding: 0px 15px;">

      <div id="printDiv" style="width: 50%;margin-left: 25%;">
        <section ref="print">
          <div style="width: 90%;margin-left: 5%;line-height:2;font-size: 20px;">
            
            <div id="extra" style="page-break-before: always;">
              <hr id="printHidden">
              <div style="color: #000000;font-size: 16px;">附件：协查信息表
                <el-button v-if="associate.assistOrgId == currentOrgId && !isOpenSendBack" @click="isOpenSendBack=true"
                           style="float: right" type="danger" size="mini" round>退回
                </el-button>
                <span v-if="isOpenSendBack" style="float: right">
                <el-button data-toggle='modal' href="#modal-send-back" type="success" size="mini" round>确定</el-button>
                <el-button @click="isOpenSendBack=false" size="mini" round>取消</el-button>
              </span>
              </div>
              <div v-for="(value,index) in dynamicTable" style="padding-bottom: 10px;">
                <div style="font-size:16px">{{value.table_name}}</div>

                <el-table
                  :data="associate.tableDataList[value.table_key]"
                  border
                  style="width: 100%; border: 1px solid #ebeef5;">
                  <el-table-column v-for="(item,idx) in value.column_key" :key="idx" :label="item.column" width="auto"
                                   :property="item.key" align="center" :cell-style="timeStyle">
                    <template slot-scope="scope">{{scope.row[scope.column.property]}}</template>
                  </el-table-column>

                  <el-table-column v-if="isOpenSendBack" align="center" prop="id" label="操作">
                    <template slot-scope="scope"><input type='checkbox' name='checkBox1' :value=scope.row.id>
                    </template>
                  </el-table-column>
                </el-table>

              </div>
            </div>
          </div>
        </section>
      </div>

    </div>

  </div>
</template>

<script>
  import vBreadcrumb from '../../../components/common/Breadcrumb'
  import vModal from '../../../components/common/modal'
  import vTable from '../../../components/common/table'

  export default {
    name: "associateInfo",
    components: {vBreadcrumb, vTable, vModal},
    data() {
      return {
        vBreadCrumbData: [
          {name: '详情', url: '#'},
        ],
        associate: {
          associateContent: {
            title: "",
            receiver: "",
            content: "",
            contacts: "",
            phone: "",
            fax: "",
            email: "",
            createOrgName: "",
            time: ""
          },
          tableDataList: [],
        },
        dynamicTable: [],
       
      }
    },
    methods: {
      printContent(){
        this.$print(this.$refs.print)
      },
     
    },
  }
</script>
<style lang="scss">
  @import "../../../../static/print/print.css";
  #associateInfo {
    .modal-body {
      min-height: auto;
    }

    .el-table__header{
      table-layout: auto;
    }
    .el-table__body{
      table-layout: auto!important;
    }
    .el-table--border th, .el-table--border td{
      border-right: 1px solid #ebeef5;
    }
    .el-table th, .el-table td{
      padding: 0px;
      word-wrap: normal!important;
      width: auto!important;
      word-break: break-all!important;
    }
    .el-table .cell{
      padding-right: 0px;
    }
  }
</style>