how to iterate over a record object about shapefile

[mbostock]

I’ve redesigned this library to use promises to make it (hopefully) easier to stream shapefiles. As before, there are two ways to do it. The easiest is to just load the whole file in memory using shapefile.read:

shapefile.read("example.shp")
  .then((collection) => console.log(collection))
  .catch((error) => console.error(error.stack));

If you prefer, you can use source.record to instead iterate over each record as a streaming API. This is more efficient because it avoids loading the whole shapefile into memory. For example:

shapefile.open("example.shp")
  .then((source) => source.header()
    .then((header) => console.log(header))
    .then(function repeat() { return source.record()
      .then((record) => record && (console.log(record), repeat())); })
    .catch((error) => source.close().then(() => { throw error; }))
    .then(() => source.close()))
  .catch((error) => console.error(error.stack));