Chart.js V2: Add prefix or suffix to tooltip label

Question

In Chart.js V1.0, I would add tooltipTemplate: \"<%if (label){%><%=label %>: <%}%><%= \'€\' + value %>\" to add a euro symbol as prefix

Answer 1

See if it helps:

        var config = {
            options: {
                tooltips: {
                    callbacks: {
                        title: function (tooltipItem, data) { return data.labels[tooltipItem[0].index]; },
                        label: function (tooltipItem, data) {
                            var amount = data.datasets[tooltipItem.datasetIndex].data[tooltipItem.index];
                            var total = eval(data.datasets[tooltipItem.datasetIndex].data.join("+"));
                            return amount + ' / ' + total + ' ( ' + parseFloat(amount * 100 / total).toFixed(2) + '% )';
                        },
                        //footer: function(tooltipItem, data) { return 'Total: 100 planos.'; }
                    }
                },
            }
        };