te')); return $arr; } /* 遍历用户所有主题 * @param $uid 用户ID * @param int $page 页数 * @param int $pagesize 每页记录条数 * @param bool $desc 排序方式 TRUE降序 FALSE升序 * @param string $key 返回的数组用那一列的值作为 key * @param array $col 查询哪些列 */ function thread_tid_find_by_uid($uid, $page = 1, $pagesize = 1000, $desc = TRUE, $key = 'tid', $col = array()) { if (empty($uid)) return array(); $orderby = TRUE == $desc ? -1 : 1; $arr = thread_tid__find($cond = array('uid' => $uid), array('tid' => $orderby), $page, $pagesize, $key, $col); return $arr; } // 遍历栏目下tid 支持数组 $fid = array(1,2,3) function thread_tid_find_by_fid($fid, $page = 1, $pagesize = 1000, $desc = TRUE) { if (empty($fid)) return array(); $orderby = TRUE == $desc ? -1 : 1; $arr = thread_tid__find($cond = array('fid' => $fid), array('tid' => $orderby), $page, $pagesize, 'tid', array('tid', 'verify_date')); return $arr; } function thread_tid_delete($tid) { if (empty($tid)) return FALSE; $r = thread_tid__delete(array('tid' => $tid)); return $r; } function thread_tid_count() { $n = thread_tid__count(); return $n; } // 统计用户主题数 大数量下严谨使用非主键统计 function thread_uid_count($uid) { $n = thread_tid__count(array('uid' => $uid)); return $n; } // 统计栏目主题数 大数量下严谨使用非主键统计 function thread_fid_count($fid) { $n = thread_tid__count(array('fid' => $fid)); return $n; } ?>html - How to check a table is empty or not using javascript - Stack Overflow

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    So i have a script like this to make a 2x2 table by javascript

    function createtable(){
          var tbl = document.getElementById('x');
            if (tbl.contains()==false){
              tbl.setAttribute('border', '1');
              var tbdy = document.createElement('tbody');
              for (var i = 0; i < 2; i++) {
                var tr = document.createElement('tr');
                for (var j = 0; j < 2; j++) {         
                    var td = document.createElement('td');
                    tr.appendChild(td);
                    td.style.height='50px';
                    td.style.width='50px';
                }
                tbdy.appendChild(tr);
              }
              tbl.appendChild(tbdy);
        }

<form>
    <input type="button" value="Create Table" onclick="createtable()"> <br>
</form>
<table id="x"> </table>

    I want to check if table x contains anything or not to create itself. Im trying to use the contains() to check but it doesnt work.

    So i have a script like this to make a 2x2 table by javascript

    function createtable(){
          var tbl = document.getElementById('x');
            if (tbl.contains()==false){
              tbl.setAttribute('border', '1');
              var tbdy = document.createElement('tbody');
              for (var i = 0; i < 2; i++) {
                var tr = document.createElement('tr');
                for (var j = 0; j < 2; j++) {         
                    var td = document.createElement('td');
                    tr.appendChild(td);
                    td.style.height='50px';
                    td.style.width='50px';
                }
                tbdy.appendChild(tr);
              }
              tbl.appendChild(tbdy);
        }

<form>
    <input type="button" value="Create Table" onclick="createtable()"> <br>
</form>
<table id="x"> </table>

    I want to check if table x contains anything or not to create itself. Im trying to use the contains() to check but it doesnt work.

    • javascript
    • html
    • html-table
    • is-empty
    Share Improve this question edited Dec 21, 2018 at 18:01 benvc 15.1k4 gold badges38 silver badges57 bronze badges asked Oct 30, 2018 at 5:11 Phạm TríPhạm Trí 611 gold badge1 silver badge4 bronze badges 1
    • What do you mean by contains "anything"? Child elements, text? – skyline3000 Commented Oct 30, 2018 at 5:20
    Add a ment  | 

    6 Answers 6

    Reset to default 6

    You can check the number of rows in the table:

    var x = document.getElementById("myTable").rows.length;

    See reference here: https://www.w3schools./jsref/coll_table_rows.asp

    Using this:

    var tbl = document.getElementById('x');
if (tbl.rows.length == 0) {
   // empty
}

    If you want to check if there are any inside table do this 

    document.getElementById("myTable").rows.length

    More info here

    you can Check the Row Counts 

    var tbl = document.getElementById('x');
if(tbl.rows.length==0){
}

    if the tbl.rows.length is 0 that means the table don't have any rows

    There are multiple ways. One of way, you can use childElementCount property.

    if (tbl.childElementCount==0)
{

}

    For more details you can refere link

    In this case, since there are no child elements or text nodes in your table, you can just check to see if the innerHTML property is falsy. This prevents your createtable function from appending additional children after the function has been run once. For example:

    function createtable() {
  var tbl = document.getElementById('x');
  if (!tbl.innerHTML) {
    var tbdy = document.createElement('tbody');
    tbl.setAttribute('border', '1');
    for (var i = 0; i < 2; i++) {
      var tr = document.createElement('tr');
      for (var j = 0; j < 2; j++) {
        var td = document.createElement('td');
        tr.appendChild(td);
        td.style.height = '50px';
        td.style.width = '50px';
      }
      
      tbdy.appendChild(tr);
    }
    
    tbl.appendChild(tbdy);
  }
}
    <form>
  <input type="button" value="Create Table" onclick="createtable()">
  <br>
</form>
<table id="x"></table>

    Plain javascript:

    !![].length

    or use Lodash

    _.head([]);
// => undefined

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