How to select all checkboxes? [duplicate]

This question already has an answer here:

• Select all checkboxes with jQuery 13 answers

I have written code like

       <div style="margin-left:12px;"><input type="checkbox" id="chkbox" /> <span style="margin-left:5px; position:relative; top:2px;" id="lblchkbox">Select All</span></div>

       <table id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction" border="0">
            <tr>
                <td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_0" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$0" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_0">Alabama</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_1" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$1" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_1">Alaska</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_2" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$2" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_2">Arizona</label></td>
            </tr><tr>
                <td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_3" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$3" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_3">Arkansas</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_4" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$4" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_4">California</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_5" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$5" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_5">Colorado</label></td>
            </tr><tr>
                <td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_6" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$6" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_6">Connecticut</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_7" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$7" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_7">Delaware</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_8" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$8" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_8">District of Columbia</label></td>
            </tr><tr>
                <td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_9" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$9" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_9">Florida</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_10" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$10" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_10">Georgia</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_11" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$11" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_11">Hawaii</label></td>
            </tr><tr>
                <td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_12" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$12" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_12">Idaho</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_13" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$13" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_13">Illinois</label></td><td><input id="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_14" type="checkbox" name="ctl00$cphAgents$UploadDoc$ctlJurisdiction1$chklJurisdiction$14" /><label for="ctl00_cphAgents_UploadDoc_ctlJurisdiction1_chklJurisdiction_14">Indiana</label></td>
            </tr><tr>
            ...
            </tr>
            </table>

Now I want that when I will check the checkbox with id "chkbox" then all the checkboxes in the table should be checked and if it is unchecked then all checkboxes in the table should be unchecked...

Please help !!!