row_count =  $('#my_table').find('tr').length;
column_count =  $('#my_table').find('td').length / row_count;

row_count =  $('#my_table').find('tr').length;
column_count =  $('#my_table').find('td').length / row_count;

我需要一种在AJAX返回中做到这一点的方法，所以我写了这篇文章:

<p id="num_results">Number of results: <span></span></p>

<div id="results"></div>

<script type="text/javascript">
$(function(){
    ajax();
})

//Function that makes Ajax call out to receive search results
var ajax = function() {
    //Setup Ajax
    $.ajax({
        url: '/path/to/url', //URL to load
        type: 'GET', //Type of Ajax call
        dataType: 'html', //Type of data to be expected on return
        success: function(data) { //Function that manipulates the returned AJAX'ed data
            $('#results').html(data); //Load the data into a HTML holder
            var $el = $('#results'); //jQuery Object that is holding the results
            setTimeout(function(){ //Custom callback function to count the number of results
                callBack($el);
            });
        }
    });
}

//Custom Callback function to return the number of results
var callBack = function(el) {
    var length = $('tr', $(el)).not('tr:first').length; //Count all TR DOM elements, except the first row (which contains the header information)
    $('#num_results span').text(length); //Write the counted results to the DOM
}
</script>

显然，这是一个简单的例子，但它可能有帮助。

我发现这工作真的很好，如果你想要计数行，而不计算th和表中的任何行:

var rowCount = $("#tableData > tbody").children().length;

好吧，我从表中获得attr行，并获得该集合的长度:

$("#myTable").attr('rows').length;

我认为jQuery不太管用。

var trLength = jQuery('#tablebodyID >tr').length;