Demo for an SO answer

SO answer: http://stackoverflow.com/questions/12455699/show-hide-table-column-with-colspan-using-jquery

by kamiolaz

HTML

<div>
    <br/>
    <input type="submit" value="Hide Associate" />
    
    <input type="submit" value="Show Associate" />
    
    <br/>
    
    <table class="resultGridTable" cellspacing="0" id="detailContentPlaceholder_grdTransactions"
        style="border-collapse: collapse;">
        <tr>
            <th scope="col">
                &nbsp;
            </th>
            <th colspan='4' class='tableColGroupAssociate'>
                Associate Info
            </th>
            <th colspan='5' class='tableColGroupTransaction'>
                Financial Info
            </th>
        </tr>
        <tr class=''>
            <th>
                Line #
            </th>
            <th scope="col">
                EmpID
            </th>
            <th scope="col">
                SID
            </th>
            <th scope="col">
                First&#160;Name
            </th>
            <th scope="col">
                Last&#160;Name
            </th>
            <th scope="col">
                Type
            </th>
            <th scope="col">
                App ID
            </th>
            <th scope="col">
                Batch ID
            </th>
            <th scope="col">
                Correlation&#160;ID
            </th>
            <th scope="col">
                Transaction ID
            </th>
        </tr>
        <tr>
            <td>
                1
            </td>
            <td>
                123
            </td>
            <td>
                1234
            </td>
            <td>
                Sandy
            </td>
            <td>
                Taylor
            </td>
            <td>
                P Adj
            </td>
            <td>
                1
            </td>
            <td>
                <a id="detailContentPlaceholder_grdTransactions_HyperLink1_0" onclick="setBatchTransactionValue();">
                    1</a>
            </td>
            <td>
                1
            </td>
     ...

CSS

td
{
    margin: 0 10px 0 10px;
    border: 1px solid blue;
}

th
{
    margin: 0 10px 0 10px;
    border: 1px solid blue;
    font: bold 12pt Arail;
}

JavaScript

$("input").on("click", function(e){
    e.preventDefault();
    
    var label = $(".resultGridTable .tableColGroupAssociate"),
        colspan = parseInt(label.attr("colspan"), 10),
        associate = $("tr:gt(0)")
                        .find("th:gt(0):lt("+ colspan +"), td:gt(0):lt("+ colspan +")")
                        .add(label);
    
    if($(this).val() == 'Hide Associate') associate.hide();
        else associate.show();
});