Paging search results

Стаття
10/28/2020

When you call any of the Bing APIs (for example, the Web Search API or Image Search API), the API returns a list of results. The list is a subset of the total number of results that may be relevant to the query. To get the estimated total number of available results, access the answer object's totalEstimatedMatches field.

The following example shows the totalEstimatedMatches field for News Search API.

{
  "_type": "News",
  "readLink": "https://<host>/api/v7.0/news/search?q=Sports",
  "queryContext": {
    "originalQuery": "Sports"
  },
  "totalEstimatedMatches": 118000,
  "value": [. . .]
}

The estimated number of matches is only an estimate and may likely change from request to request.

Paging through search results

To page through the results, use the count and offset query parameters.

The count parameter specifies the number of results to return in the response. The maximum number of results that you may request in the response is API specific (see Count values by API). For example, the maximum count value that you may specify for the Image Search API is 150.

The offset parameter specifies the number of results to skip. The offset is zero-based and should be less than (totalEstimatedMatches - count).

If your user interface presents 20 news articles per page, set count to 20 and offset to 0 to get the first page of results. For each subsequent page, increment offset by 20 (for example, 20, 40).

The following shows an example that requests 20 news articles beginning at offset 40.

https://<host>/api/v7.0/news/search?q=sailing&count=20&offset=40&mkt=en-us

Because each API sets a default value for count, you may specify only offset. For example, if the News Search API’s default count is 20, you only need to include the offset query parameter.

https://<host>/api/v7.0/news/search?q=sailing&offset=40&mkt=en-us

Count values by API

The following table list the default and maximum count value per API.

API	Default	Maximum
Web Search	10	50
Image Search	35	150
News Search	10	100
Video Search	35	105

For the Image, News, and Video APIs, paging applies to only the general search endpoint. For example, you may not use paging with the trending endpoints.

Paging web search results

The Web Search API returns results that include webpages and may include other answers like images, videos, and news. When you page the search results, you are paging the webpage results and not the other answers. For example, if you set count to 15, Bing returns 15 webpage results, but may return 35 images and 4 news articles.

The answers that Bing returns from page to page is unknown. For example, Bing may include news on the first page but not the second page, or vise-versa.

Note that if you specify the responseFilter query parameter and do not include Webpages in the list of filters, you should not use the count and offset parameters.

Paging image and video results

Typically, if you page 30 images at a time, you set the offset query parameter to 0 on your first request, and increment offset by 30 on each subsequent request. However, some results in the subsequent response may be duplicates of the previous response. For example, the first two images in the response may be the same as the last two images from the previous response.

To eliminate duplicate results, set the offset query parameter to the value in the nextOffset field of the ImageAnswer object. The nextOffset value adjusts for duplicates.

{
  "_type": "Images",
  "readLink": "images/search?q=nurburgring",
  "webSearchUrl": "https://www.bing.com/images/search?q=nurburgring&FORM=OIIARP",
  "queryContext": {. . .},
  "totalEstimatedMatches": 933,
  "pivotSuggestions": [. . .],
  "queryExpansion": [. . .],
  "relatedSearches": [. . .],
  "nextOffset": 65,
  "currentOffset": 0,
  "value": [. . .]
}

For example, if you want to page 30 images at a time, you'd set count to 30 and offset to 0 in your first request. In your next request, you'd set count to 30 and offset to the value of nextOffset. The value of nextOffset will be 30 if there are no duplicates or it may be 32 if there are 2 duplicates.

Use the same technique when paging videos.

Next steps

Learn about using rank to display search results.

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