SearchJob Class

Use to search indexes or to search without an index.

dtSearch.Engine.JobBase | dtSearch.Engine.SearchJob

public class SearchJob : JobBase;

Remarks

Search criteria

There are three components to the search request that can be included in a SearchJob:

(1) Request: The search request, which can be in the "boolean", "all words", or "anywords" syntax, depending on the value of SearchFlags.

(2) BooleanConditions: A string in the boolean syntax expressing any conditions that must be satisfied in addition to whatever is in Request. This provides a way to add boolean conditions (such as field criteria) to a user-supplied query, which may be in the all words or any words syntax.

(3) FileConditions: A string expressing conditions such as filename matches, file size matches, etc., that documents must satisfy.

For more information, see: Search Requests Overview

Monitoring and cancelling searches

To receive callbacks during a search with the name of each document as it is found, create an object that implements the ISearchStatusHandler interface and attach it to the SearchJob's StatusHandler.

In server applications, to limit the amount of time and resources a search can consume, use TimeoutSeconds, MaxFilesToRetrieve, and AutoStopLimit.

For more information, see: Limiting Searches.

Search filters

A SearchFilter represents a set of documents that can be returned in a search. To limit a search to the documents in a SearchFilter, set up a SearchFilter object with the filter to use, and assign it to SearchJob.SearchFilter. Example:

using (dtSearch.Engine.SearchFilter filter = new SearchFilter()) { int iIndex = filter.AddIndex(m_indexPath); // This will limit the search to documents with DocIds between 1 and 9999. filter.SelectItems(iIndex, 1, 9999, true); searchJob.SearchFilter = filter; // Now when searchJob is executed, only documents identified by searchFilter can be // retrieved. ...

To generate a search filter based on the results of a search, pass the SearchFilter to the SearchJob.Execute method, like this:

using (SearchJob searchJob = new SearchJob()) using (SearchResults searchResults = new SearchResults()) using (SearchFilter resultsFilter = new SearchFilter()) { searchJob.IndexesToSearch.Add(IndexPath); searchJob.Request = request; searchJob.Execute(searchResults, resultsFilter); // Now resultsFilter will select all of the documents that were found // in the search. // ... }

To optimize the search to generate a SearchFilter only, set the flag dtsSearchFastSearchFilterOnly in SearchJob.

After the search, every document retrieved in the search will be selected in the output search filter. The generated search filter can then be used to limit a subsequent search, which can be useful for implementing a "search within these results" feature.

SearchJob.MaxFilesToRetrieve does not affect the generated output SearchFilter, which will include every item retrieved in the search. However, if AutoStopLimit causes the search to terminate before it is complete, then only items found before the search stopped will be selected in the SearchFilter.

For more information, see: Limiting searches with SearchFilters.

IDisposable

SearchJob, SearchResults, and SearchFilter all require the IDisposable Pattern.

Example

// Allocate SearchJob and SearchResults to store results using (dtSearch.Engine.SearchJob searchJob = new dtSearch.Engine.SearchJob()) using (SearchResults results = new SearchResults()) { searchJob.Request = searchRequest.Text; searchJob.IndexesToSearch.Add(indexPath.Text); searchJob.MaxFilesToRetrieve = 100; searchJob.SearchFlags = SearchFlags.dtsSearchDelayDocInfo; searchJob.Execute(results); searchJob.Execute(); if (searchJob.Errors.Count > 0) // ... display error messages ... else { // ... display search results ... } }

Topics

Topic	Description
JobBase Members	The following tables list the members exposed by JobBase.
JobBase Properties	The properties of the JobBase class are listed here.

SearchJob Class

Topic	Description
SearchJob Members	The following tables list the members exposed by SearchJob.
SearchJob Methods	The methods of the SearchJob class are listed here.
SearchJob Properties	The properties of the SearchJob class are listed here.

SearchJob Methods

SearchJob Class

SearchJob Class	Description
Execute	Executes the search and returns when the search is complete.

JobBase Properties

Show:Inherited

No members matching the current filter

JobBase Properties	Description
Errors	(Inherited from JobBase)
TimeoutSeconds	Set to a non-zero value to make the job terminate automatically after a specified number of seconds. (Inherited from JobBase)

SearchJob Class

SearchJob Class	Description
AutoStopLimit	Set to a non-zero value to make the search automatically stop when this many documents were found.
BooleanConditions	Additional boolean conditions that a document must meet to be retrieved in a search.
ExcludeFilters	Filename filters to exclude documents from the search in an unindexed search.
FieldWeights	Specify a relevance weight for hits that occur in listed fields (example: Subject:10,HtmlTitle:20)
FileConditions	File conditions that a document must meet to be retrieved in a search.
FileCount	After a search, contains the number of files retrieved (this is the total number of documents matched, regardless of the MaxFilesToRetrieve setting).
FoldersToSearch	In an unindexed search, the directories or files to search.
Fuzziness	If non-zero, the engine will match words that are close to but not identical to a search term.
HitCount	After a search, contains the number of hits in all files retrieved.
IncludeFilters	Filename filters to select documents to search in an unindexed search.
IndexCache	Use an IndexCache for this SearchJob
IndexesToSearch	The full path of each index to search.
MaxFilesToRetrieve	Limit the maximum size of search results to a specified number of files.
Request	What to search for.
SearchFilter	Apply a search filter to the search that can be used to exclude or permit specified documents to be returned in search results.
SearchFlags	Flags controlling various search options.
StatusHandler	Object to receive callback notifications when documents are found.
UnindexedSearchFlags	Flags controlling various search options.