小编sr.*_*r.u的帖子

I'm trying to add an onClick event to my D3 barChart and perform some actions depending on the clicked bar, but I'm unable to get the event's 'data' parameter (undefined). Am I missing something? Thanks in advance!

    var data = [{
        letter: 'A',
        frequency: 5
    }, {
        letter: 'B',
        frequency: 8
    }];

    var margin = {
            top: 20,
            right: 20,
            bottom: 30,
            left: 40
        },
        width = 960 - margin.left - margin.right,
        height = 500 - margin.top - margin.bottom;

    var …