The criteria to apply when searching previously indexed app content.
- iOS 10.0+
- macOS 10.12+
- Core Spotlight
A search query object manages the criteria to apply when searching app content that you have previously indexed using the Core Spotlight APIs.
To search app content that you’ve indexed, create a
CSSearch object by specifying a formatted query string and an array of attribute names that correspond to properties defined by
CSSearchable (to learn more about indexing items in your app, see Index App Content). After you start the query, you receive batches of matching
CSSearchable objects in the handler you implement for the
found property. When the query has returned all the items it found, it calls your completion handler and passes
nil to indicate that it completed successfully.
Creating a Query String
Query strings operate on the values associated with a property in a
CSSearchable object. A query string can take either of the following forms:
Name operator value[modifiers]
Range(attribute Name, min Value, max Value)
In both forms,
attribute represents the name of a property. The
attribute form is well suited to a wide range of matches, especially when you take advantage of
operator to combine predicates (possible operators are listed in Table 1) and
modifiers to specify types of comparisons to perform on a property’s
value (possible modifiers are listed in Table 2). In addition to specifying modifiers, you can also use the
* character as a wild card that lets you match substrings in various locations within a string. Use the
In form to match numeric values associated with the
attribute property that are within the range specified by
For example, consider an app that uses the code shown below to index searchable items with titles that start with the string "Searchable":
To match all searchable items that have titles that begin with “Searchable,” this app can create the following query string, which uses the
= operator and the
* wild card character.
Working with Operators, Modifiers, and the Wild Card
Operators let you specify the relationship between a value and a property, such as equal or not equal. Modifiers let you specify types of text-based comparisons, such as case insensitive or word-based.
You can create a query string using the operators listed in Table 1.
Less than (used only for numeric and date values)
Greater than (used only for numeric and date values)
Less than or equal (used only for numeric and date values)
Greater than or equal (used only for numeric and date values)
To specify one or more types of text-based comparison, you can use the modifiers listed in Table 2.
Use this modifier...
To specify a comparison that is...
Insensitive to diacritical marks.
Word-based. In addition, the comparison detects transitions from lower-case to upper-case.
Performed on the tokenized value. For example, values passed directly from a search field are tokenized.
Table 3 lists some examples of modifier usage.
title == “Paris”
“Paris”, but not “paris” or “I love Paris”.
title == “Paris”c
“Paris” and “paris”, but not “I love Paris”.
title == “Paris”wc
“Paris”, “paris”, “I love Paris”, and “paris- france.jpg”, but not “Comparison”.
title == ‘Window’w
“MyWindowClass” and “Broken Window”, but not “NSWindow”.
authorNames == "Frédéric"
“Frédéric”, but not “Frederic”.
authorNames == "Frédéric"cd
“Frédéric” and “Frederic”, regardless of the word case.
Although you can use the wild card character (
*) to match a substring at the beginning, end, or interior of a string, it’s often a better idea to use the
w modifier to do smart word matching instead. Table 4 lists some examples of using the wild card in a query string.
title == “paris*”
Values that begin with “paris”, such as “paris” and “parisol”, but not “comparison”.
title == “*paris”
Values that end with “paris”.
title == “paris”
Values that contain "paris" anywhere within the string, such as “paris”, “parisol”, and “Comparison”.
title == ‘paris’
Values that are exactly equal to “paris”.
You can combine queries by using a C-like syntax for AND (
&&) and OR (
||). For example, you might create the following query to match audio items that were authored by Steve:
You can also use parentheses to group query matching. For example, to match audio or video items that were authored by either Steve or Kevin, you can create the following query string:
Matching Dates and Times
You can create queries that use date and time as the search value. Date and time values are formatted as floating-point values that are compatible with
CFDate, and represent seconds relative to January 1, 2001.
In addition, you can use
$time values to specify values relative to the current time. For example, to restrict a search to match only the searchable items that completed in the last 10 days, you might use the following query:
Table 5 lists the properties of
$time that you can use to specify dates and time periods relative to the current time.
The current date and time
The current date
The week preceding the current week
The current week
The current month
The current year
The date and time that results when NUMBER, a positive or negative value that represents seconds, is added to the current time
The date that results when NUMBER, a positive or negative value that represents days, is added to the current day
The date that results when NUMBER, a positive or negative value that represents weeks, is added to the current week
The date that results when NUMBER, a positive or negative value that represents months, is added to the current month
The date that results when NUMBER, a positive or negative value that represents years, is added to the current year
The date represented by parsing the specified ISO-8601-STR compliant string
Putting It All Together
Here is an example of using
CSSearch in your app: