如何遍历数组并检查

Question

I need to loop over a data structure that looks like this:

{tags: ["stonehenge"], text: "At about 40m high, Silbury Hill is the highest prehistoric mound in Europe and about the size of one of the smaller pyramids of the Giza Necropolis in Egypt. Construction started about 2400BC and is estimated (by R J C Atkinson) to have taken 500 men working full-time about 15 years to complete. It is hard to see how a single tribe could have found this man-power; rather it seems necessary to envisage a much larger social structure. The monument is contemporary with Stonehenge and part of the Stonehenge World Heritage Site, close to Avebury. Its function is not known.", speech: "Silbury Hill, built starting in 2400 BC, is the highest prehistoric mound in Europe and about the size of one of the smaller pyramids of the Giza Necropolis in Egypt.", title: ["Silbury Hill"], themes: ["photo", "Avebury", "UNESCO WHS"], image: {url: "images/Silbury_Hill.jpg"}}, ...

and extract only those items for which the value searchTheme (eg "photo") is found in the themes object.

My function that is intended to accomplish this is:

  console.log ("ready to search for searchTheme", searchTheme,"in", items.length,  "items")

  for (var j = 0; j < items.length; j++) {
    for (var k = 0; k < items[j].themes.length; k++) 
    console.log("examining item", j, "theme", k, "which is", items[j].themes[k],"for match with", searchTheme)
    if (searchTheme == items[j].themes[k] {
      console.log ("that was a match")
      matches.push(items[k])}

    }

which returns something that looks like it's looping over the array correctly, but, for some reason, is not -- returning zero hits.

Answer 1

I went back to the bixby example repositories on Github and found a model in the facts capsule. This worked:

   for (var i = 0; i < items.length; i++) {
    if (items[i].themes) {
      for (var j = 0; j < items[i].themes.length; j++) {
        if (searchTheme == items[i].themes[j].toLowerCase()) {
          matches.push(items[i])
          break
        }
      }
    }
  }
  return matches

What's different is the second line tests to see if the theme is contained in the object. Honestly, I thought I was doing it right in my version. but this one works.