如何检查表中是否存在值并返回该行中单元格的值

Question

我需要检查整个表，如果第 1 列有值（保留），并返回找到该值的那行的单元格 0 的值。

基本上点击一个按钮，运行函数并返回找到值（REVERVED）所在行的单元格0的值。

如果可以的话，我喜欢使用普通的 javascript 而不是 jquery。

如果我实际单击该行，则以下功能将起作用。

  <input type="button" value="☑️ check if RESERVED exists" onclick="findValueInRow()"> //
  <br>
  <br>

  <table id="table2">
    <thead>
      <tr>
        <th>ID</th>
        <th>Contact</th>
        <th>Country</th>
      </tr>
    </thead>
    <tr>
      <td>1</td>
      <td>Maria Anders</td>
      <td>Germany</td>
    </tr>
    <tr>
      <td>2</td>
      <td>RESERVED</td>
      <td>Mexico</td>
    </tr>
    <tr>
      <td>1</td>
      <td>Roland Mendel</td>
      <td>Austria</td>
    </tr>
    <tr>
      <td>3</td>
      <td>Helen Bennett</td>
      <td>UK</td>
    </tr>
    <tr>
      <td>4</td>
      <td>RESERVED</td>
      <td>Canada</td>
    </tr>
    <tr>
      <td>5</td>
      <td>Giovanni Rovelli</td>
      <td>Italy</td>
    </tr>
  </table>
</body>



      function findValueInRow()
   {
    table = document.getElementById("table2");
    for(var i = 1; i < table.rows.length; i++)
     {
     table.rows[i].onclick = function()
      {
     // get the selected row index
      rIndex = this.rowIndex;
    var produtcID = this.cells[1].textContent;   
    //check to see if value RESERVED exists in the table
     if(produtcID == "RESERVED" )
      {
      alert(this.cells[0].textContent);

      }
      else{
       //my other code if the value is not found
       }//end else                    
       };
  }
   }

Answer 1

是现在吗？

function findValueInRow() {
  table = document.getElementById("table2");
  var rows = table.rows;
  for (var i = 1; i < rows.length; i++) {
    var cols = rows[i].cells;
    for (var c = 0; c < cols.length; c++) {
      if (cols[c].innerText == 'RESERVED') {
        return cols[0].innerHTML;
      }
    }
  }
  return '';
}

table {
  background:gray;
}
td, th {
  background:white;
}

<input type="button" value="☑️ check if RESERVED exists" onclick="alert(findValueInRow())">
<br>
<br>

<table id="table2">
  <thead>
    <tr>
      <th>ID</th>
      <th>Contact</th>
      <th>Country</th>
    </tr>
  </thead>
  <tr>
    <td>1</td>
    <td>Maria Anders</td>
    <td>Germany</td>
  </tr>
  <tr>
    <td>2</td>
    <td>RESERVED</td>
    <td>Mexico</td>
  </tr>
  <tr>
    <td>1</td>
    <td>Roland Mendel</td>
    <td>Austria</td>
  </tr>
  <tr>
    <td>3</td>
    <td>Helen Bennett</td>
    <td>UK</td>
  </tr>
  <tr>
    <td>4</td>
    <td>RESERVED</td>
    <td>Canada</td>
  </tr>
  <tr>
    <td>5</td>
    <td>Giovanni Rovelli</td>
    <td>Italy</td>
  </tr>
</table>