如果能看到一些HTML
我们来分析一下
适当的取消注解/注解

window.addEventListener('DOMContentLoaded', () => { // when page has loaded
  document.getElementById('getInfo').addEventListener('click', () => {
    var checkedBoxes = document.querySelectorAll('input[class="chk"]:checked'); // all checked boxes
    const values = [...checkedBoxes].map(chk => {
      const checkedRow = chk.closest("tr");
      const cellWeWant = checkedRow.querySelectorAll('td')[2]
      const textWeWant = cellWeWant.textContent; // if the text
      const valueWeWant = cellWeWant.querySelector('input').value; // if the value of an input
      // return textWeWant; // uncomment to get text
      return valueWeWant;   // comment above and uncomment to get values 
    });
    console.log(values)
  });
});

<table>
  <tbody>
    <tr>
      <td><input type="checkbox" class="chk" /></td>
      <td>Line 1</td>
      <td>Description 1 <input type="text" value="value1" /></td>
    </tr>
    <tr>
      <td><input type="checkbox" class="chk" /></td>
      <td>Line 2</td>
      <td>Description 2 <input type="text" value="value2" /></td>
    </tr>
    <tr>
      <td><input type="checkbox" class="chk" /></td>
      <td>Line 3</td>
      <td>Description 3 <input type="text" value="value3" /></td>
    </tr>
  </tbody>
</table>
<button type="button" id="getInfo">Get info</button>

我试图从你发布的内容创建一个[mcve]，但我认为它不是我们在这里谈论的jTable？

$(function() {
  $('#TableContainer').jtable({
    title: 'List',
    paging: true,
    pageSize: 10,
    sorting: true,
    defaultSorting: 'Id DESC',
    actions: {
      listAction: 'List.aspx/List'
    },
    fields: {
      Tag: {
        sorting: false,
        title: function(data) {
          return '<input type="checkbox" class="chkAll">';
        },
        width: '2.5%',
        display: function(data) {
          return '<input type="checkbox" class="chk">';
        }
      },
      ref_no: {
        title: 'Reference No.',
        width: '5%',
      },
      borrowerName: {
        title: 'Borrower Name'
      },
      lendingUnitDesc: {
        title: 'Lending Unit'
      },
      statusDesc: {
        sorting: false,
        title: 'Status',
        width: '4%'
      },
      rmName: {
        title: 'RM'
      },
      addedBy: {
        title: 'Owner'
      },
      SeniorReviewer: {
        title: 'Senior Reviewer'
      }
    },
  })

  $(".chkAll").click(function(event) {
    if (this.checked) {
      $(':checkbox').each(function() {
        this.checked = true;
      });
    } else {
      $(':checkbox').each(function() {
        this.checked = false;
      });
    }
  });
  $("#btnReassign").on("click", function() {
    var checkedBoxes = $('input[class="chk"]:checked'); // all checked boxes
    const values = [...checkedBoxes].map(function() {
      const $checkedRow = $(this).closest("tr");
      const $cellWeWant = $checkedRow.find('td').eq(2)
      const textWeWant = $cellWeWant.text(); // if the text
      const valueWeWant = $cellWeWant.find('input').val(); // if the value of an input
      // return textWeWant; // uncomment to get text
      return valueWeWant; // comment above and uncomment to get values 
    }).get();
    console.log(values)
  });
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/lib/jquery.jtable.min.js"></script>
<link href="https://cdn.jsdelivr.net/npm/[email protected]/lib/themes/metro/blue/jtable.min.css" rel="stylesheet">

<div class="site-container" style="width:100%">
  <div id="SearchRecord" style="background-color:#DEEDF8; padding:3px; border:1px solid #DDDDDD; color:#2e6894">
    &nbsp;&nbsp;Search Record : <input type="text" id="txtSearch" value="" size="40" />&nbsp;
    <input type="button" id="btnSearch" value="Filter" />&nbsp;&nbsp;
    <input type="button" id="btnFilterby" value="Filter By RM/Lending Unit" />&nbsp;&nbsp;
    <input type="button" id="btnReset" value="Reset" />&nbsp;&nbsp;
    <input type="button" id="btnReassign" value="Reassign" />&nbsp;&nbsp;
    <input type="hidden" id="lblValidation" style="color:#ff0000; font-weight:bold" />
  </div>
  <div id="TableContainer" style="width:100%"></div>
</div>
<input type="hidden" id="hdnRefNo" class="hdnRefNo" value="0" />
<div class="div-RMpopup" style="width: 98%; margin: 0 auto;">
  <div id="dvFilterModalPopUp"></div>
  <div id="dvReassignModalPopUp"></div>
</div>
<br /><br />