How to change CSV file via dropdown menu for chart.js

I currently have a graph that I am displaying information on via a CSV file. What I would like to do is change the CSV file depending on which drop down selection the user has chosen. EG - If the user selection is "TestData1" it will display the data from test_data.csv. If the selection is "TestData2", it will display the data from test_data2.csv and so on. I would like to be able to add as many drop down options and external csv files as I wish.

Currently the code works to display chart, but I can't figure out how to get it to work with the dropdown selector. I have tried the solution found at d3js dynamic csv switch from dropdown list but unfortunately it did not work for me.

Here is my code so far -

    <select name="csvGraphSelector" class="input">
        <option value="test_data">TestData1</option>
        <option value="test_data2">TestData2</option>
    </select>

    <canvas id="chart"></canvas>

<script>
function makeChart(cvcGraph) {

    var cvcGraphLabels = cvcGraph.map(function(d) {
        return d.Time;
    });

    var cvcGraphData = cvcGraph.map(function(d) {
        return +d.Bandwidth;
    });

    var chart = new Chart('chart', {

        type: "line",

        responsive: true,

        options: {
            maintainAspectRatio: true,
            legend: {
                display: false
            },
            elements: {
                point: {
                    radius: 2
                }
            },
            scales:{
                xAxes:[{
                    gridLines: {
                        display: false,
                        drawBorder: true
                    },
                    ticks: {
                        display: true,
                        autoSkip: true,
                        maxTicksLimit: 12
                    }
                }],
                yAxes:[{
                    gridLines: {
                        display: false,
                        drawBorder: false
                    },
                    ticks: {
                        display: true,
                        autoSkip: true,
                        maxTicksLimit: 3,
                        suggestedMin: 0,
                        beginAtZero: true,
                        max: 100,
                        padding: 30
                    }
                }]
            }

        },
        data: {
            labels: cvcGraphLabels,
            datasets: [{
                data: cvcGraphData,
                fill: true,
                borderColor: "#333",
                borderWidth: 2,
                backgroundColor: "#fff",
                pointBackgroundColor: "#333",
                pointBorderColor: "#fff",
                pointBorderWidth: 1
            }]  
        }

    });

}

d3
    .csv("/assets/test_data.csv")
    .then(makeChart);

</script>

Any help would be greatly appreciated.

Thanks.