Leaflet - Add a popup to GeoJSON features

leaflet-geojson-popup.js

/* This example demonstrates how to create a popup for a GeoJSON layer
 * "YOUR_FIELD_NAME" should be the name of an attribute of the GeoJSON layer.
 * Any string can be used in bindPopup(), including HTML. 
 */
function createPopup(feature, layer) {
  // code here will run when a feature on the map is clicked.
  layer.bindPopup(feature.properties.YOUR_FIELD_NAME) // show the clicked feature's attribute value in a popup
  // some other code can go here, like adding the layer to a layer group so it can be shown on a control
}

// Use jQuery's getJSON method to fetch the data from a URL
jQuery.getJSON( "http://example.com/layer1.geojson", function( json ) {
  // Use Leaflet's geoJSON method to turn the data into a feature layer
  L.geoJSON( json, {
    onEachFeature: createPopup // When each record of data is converted into a feature, call a function to add a popup
  }).addTo( mymap )
})