Standalone Examples » Tooltips #4 - placeholder parser

If you find you need to do any form of conversion of the placeholder data within the tooltips string, such as formatting a number or uppercasing a string, you can use the tooltips.placeholderParser function. See below for a simple example: it adds an exclamation mark after the label, and adds decimal points to the percentage and values.

var pie = new d3pie("pie", {
  data: {
    content: [
      { label: "Elephants", value: 1 },
      { label: "Motmots", value: 2 },
      { label: "Pikas", value: 3 },
      { label: "Jays", value: 2 },
      { label: "Rhubarb", value: 5 },
      { label: "Tennis", value: 2 },
      { label: "Chickens", value: 1 }
    ]
  },
  tooltips: {
    enabled: true,
    type: "placeholder",
    string: "{label}: {percentage}% ({value})",

    // data is an object with the three properties listed below. Just modify the properties
    // directly - there's no need to return anything
    placeholderParser: function(index, data) {
      data.label = data.label + "!";
      data.percentage = data.percentage.toFixed(2);
      data.value = data.value.toFixed(5);
    }
  }
});