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Unable to get the searched document using Lucene.net

I'm new to Lucene.net. I've a situation where I need to search the all the documents in a folder for a keyword that has been entered by the user.
I've indexed all the files in the folder and prepared a query for the keywords entered by the user and performed searching.
The problem is I could get the hits and when I tried to iterate the hits, I couldn't get the fields from the documents of the hits.
Here is my code.
public void Searching()
{
Analyzer analyzer = new StandardAnalyzer(luceneVersion.Version.LUCENE_29);
QueryParser parser = new QueryParser(luceneVersion.Version.LUCENE_29, "content", analyzer);
Query query = parser.Parse(txtSearchText.Text);
Directory directory = FSDirectory.Open(new System.IO.DirectoryInfo(txtIndexPath.Text.Trim()));
Searcher searcher = new IndexSearcher(IndexReader.Open(directory, true));
TopScoreDocCollector collector = TopScoreDocCollector.Create(100, true):
searcher.Search(query, collector);
ScoreDoc [] hits = collector.TopDocs(). ScoreDocs;
foreach (ScoreDoc hit in hits)
{
int id = hit.Doc;
float score = hit.Score;
Document doc = searcher.Doc(id);
string content = doc.Get("content"); // null
}
}
When tried to debug, the content I'm getting is null, empty.
Am I missing anything in my code, this is literally bogging me since half day all the way. Please help me out.
Thanks in advance.

I've been trying this everything whatever I could do. The problem is I've been indexing without storing the id field of the document in the index file.
Here was the code I've used while indexing.
doc.Add(new Field("id", id, Field.Store.NO, Field.Index.ANALYZED);
While it should be like the following, so that it will be available in the index file.
doc.Add(new Field("id", id, Field.Store.YES, Field.Index.ANALYZED);

Why is the Lucene.NET IndexSearcher returning zero results?

I recently started working with Lucene.NET and I have some problems: I have used an IndexWriter to index my documents in C:\\TestIndex which I guess it worked since it generated several .fnm, .frq, .cfx, .tii, .tis files.
The problem is when trying to make a simple search through them, I never get any results back. Below is the code I use,
using Lucene.Net.Documents;
using Lucene.Net.Index;
using Lucene.Net.QueryParsers;
using Lucene.Net.Search;
using Lucene.Net.Store;
using Lucene.Net.Util;
//Provide the directory where index is stored
Directory directory = FSDirectory.Open(newSystem.IO.DirectoryInfo(#"C:\\TestIndex"));
IndexReader indexReader = IndexReader.Open(directory, true);
Searcher indexSearch = new IndexSearcher(indexReader);
Analyzer std = new StandardAnalyzer(Version.LUCENE_29);
QueryParser parser = new QueryParser(Version.LUCENE_29, "text", std);
Query qry = parser.Parse("morning");
// true opens the index in read only mode
Searcher srchr = new IndexSearcher(IndexReader.Open(directory, true));
TopScoreDocCollector cllctr = TopScoreDocCollector.Create(100, true);
ScoreDoc[] hits = cllctr.TopDocs().ScoreDocs;
srchr.Search(qry, cllctr);
for (int i = 0; i < hits.Length; i++)
{
int docId = hits[i].Doc;
float score = hits[i].Score;
Document doc = srchr.Doc(docId);
Console.WriteLine("Searched from Text: " + doc.Get("text"));
}
I tried several approaches but I never get any result. Do you have any idea?
Below is indexing code,
IndexWriter indexWriter =
new IndexWriter(
luceneDir,
new StandardAnalyzer(Version.LUCENE_29),
true,
IndexWriter.MaxFieldLength.UNLIMITED);
string[] listOfFiles = Directory.GetFiles(#"C:\Projects\lucene.net-trunk\build\vs2010\demo\MyTestProject\TestDocs");
foreach (string s in listOfFiles)
{
String content = File.ReadAllText(s);
Document doc = new Document();
String title = s;
// adding title field
doc.Add(new Field("title", title, Field.Store.YES, Field.Index.NOT_ANALYZED));
doc.Add(new Field("content", content, Field.Store.YES, Field.Index.ANALYZED));
indexWriter.AddDocument(doc);
}
indexWriter.Optimize();
indexWriter.Dispose();

Use luke to inspect the index to ensure it has data also you can perform searches to validate your search criteria
http://www.getopt.org/luke/
EDIT - (Luke will work with lucene and lucene.net indexes you will need to install java to use)
EDIT
Update the line
Lucene.Net.QueryParsers.QueryParser parser = new Lucene.Net.QueryParsers.QueryParser(Lucene.Net.Util.Version.LUCENE_29, "text", std);
With
Lucene.Net.QueryParsers.QueryParser parser = new Lucene.Net.QueryParsers.QueryParser(Lucene.Net.Util.Version.LUCENE_29, "content", std);
You have set the default search field to text which doesn't exist
Also you are trying to fetch the wrong field in your console.write line

Make sure you use the same analyzer when indexing and searching (in your case it's StandardAnalyzer I guess):
using Lucene.Net.Analysis;
using Lucene.Net.Documents;
using Lucene.Net.Index;
using Lucene.Net.Store;
...
Directory directory = FSDirectory.Open(new System.IO.DirectoryInfo(#"C:\\TestIndex"));
var writer = new IndexWriter(
directory,
new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29),
true,
new MaxFieldLength(int.MaxValue));
UPDATE
I'm using a slightly different approach for searching but, anyway, maybe you need to swap these two lines:
ScoreDoc[] hits = cllctr.TopDocs().ScoreDocs;
srchr.Search(qry, cllctr);
So it becomes:
srchr.Search(qry, cllctr);
ScoreDoc[] hits = cllctr.TopDocs().ScoreDocs;
meaning that the collector first collects the results when the search is executed and then you get your scored documents via the collector instance.

Could you try explicitely specifying the field you're searching? for example:
Lucene.Net.QueryParsers.QueryParser parser = new Lucene.Net.QueryParsers.QueryParser(Lucene.Net.Util.Version.LUCENE_29, "text", std);
Lucene.Net.Search.Query qry = parser.Parse("content: morning");
I think that Lucene requires you to tell it on which field(s) (title, content...) you want to run your query.

Lucene.net and partial "starts with" phrase search

I'm looking to build an auto-complete textbox over a large quantity of city names. Search functionality is as follows: I want a "Starts with" search over a multi-word phrase. For example, if user has typed in "chicago he", only locations such as "Chicago Heights" need to be returned.
I'm trying to use Lucene for this. I'm having issues understanding how this needs to be implemented.
I've tried what I think is the approach that should work:
I've indexed locations with KeywordAnalyzer (I've tried both TOKENIZED and UN_TOKENIZED):
doc.Add(new Field("Name", data.ToLower(), Field.Store.YES, Field.Index.TOKENIZED, Field.TermVector.NO));
And search for them via the following (I've also tried a variety of other queries/analyzers/etc):
var luceneQuery = new BooleanQuery();
var wildcardQuery = new WildcardQuery(new Term("Name", "chicago hei*"));
luceneQuery.Add(wildcardQuery, BooleanClause.Occur.MUST);
I'm not getting any results. Would appreciate any advice.

To do that you need to index your field with the Field.Index.NOT_ANALYZED setting, which is the same as the UN_TOKENIZED you use, so it should work. Heres a working sample I quickly made up to test. Im using the latest version available on Nuget
IndexWriter iw = new IndexWriter(#"C:\temp\sotests", new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29), true);
Document doc = new Document();
Field loc = new Field("location", "", Field.Store.YES, Field.Index.NOT_ANALYZED);
doc.Add(loc);
loc.SetValue("chicago heights");
iw.AddDocument(doc);
loc.SetValue("new-york");
iw.AddDocument(doc);
loc.SetValue("chicago low");
iw.AddDocument(doc);
loc.SetValue("montreal");
iw.AddDocument(doc);
loc.SetValue("paris");
iw.AddDocument(doc);
iw.Commit();
IndexSearcher ins = new IndexSearcher(iw.GetReader());
WildcardQuery query = new WildcardQuery(new Term("location", "chicago he*"));
var hits = ins.Search(query);
for (int i = 0; i < hits.Length(); i++)
Console.WriteLine(hits.Doc(i).GetField("location").StringValue());
Console.WriteLine("---");
query = new WildcardQuery(new Term("location", "chic*"));
hits = ins.Search(query);
for (int i = 0; i < hits.Length(); i++)
Console.WriteLine(hits.Doc(i).GetField("location").StringValue());
iw.Close();
Console.ReadLine();

The only way to guarantee a "starts with" search is to put a delimiter at the beginning of the indexed string, so "diamond ring" is indexed like "lucenedelimiter diamond ring lucenedelimiter". This prevents a search turning up "the famous Diamond Ridge Resort" from turning up in a search for "diamond ri*".

trouble with TermFreqVector in lucene.net

i've been trying to get the frequency of terms of a document usin TermFreqVvector,
here is my code,
LuceneStore.Directory dir = LuceneStore.FSDirectory.GetDirectory("e:/indexDir", true);
IndexWriter writer = new IndexWriter(dir, new StandardAnalyzer(), true);
Document doc = new Document();
doc.Add(new Field("Content", "This is a beautiful house", Field.Store.YES, Field.Index.TOKENIZED, Field.TermVector.YES));
writer.AddDocument(doc);
writer.Optimize();
writer.Close();
IndexReader reader = IndexReader.Open(dir);
TermFreqVector termFreq = reader.GetTermFreqVector(0, "content");
string[] term = termFreq.GetTerms();
but i get the error msg "Object reference not set to an instance of an object"
on the line
string[] term = termFreq.GetTerms();
can anyone help!!!!!

The GetTermFreqVector method is documented to return null if the storeTermVector flag hasn't been set - are you sure it's set in your case?
EDIT: I've just noticed that you're using "Content" as the field name in the constructor, and then "content" when you're asking for the term frequency vector. That could easily be the problem if field names are case-sensitive. I suggest you create a constant string used everywhere you want to refer to the field, for consistency.

Lucene Searcher return only one match result

My search text goes as "ma" and i have two lucene document which have ma as the text in it. But in return i only get one document.
Below is the code :
//adding deocument
document.Add(new Field("Text",text,Field.Store.YES, Field.Index.TOKENIZED));
//search logic :
IndexReader reader = IndexReader.Open(GetFileInfo(indexName));
//create an index searcher that will perform the search
IndexSearcher searcher = new IndexSearcher(reader);
//List of ID
List<string> searchResultID = new List<string>();
//build a query object
QueryParser parser = new QueryParser("Text", analyzer);
parser.SetAllowLeadingWildcard(true);
Query query = parser.Parse(searchText);
//execute the query
Hits hits = searcher.Search(query);

Maybe you could use luke. It's a useful diagnostic tool that can display the contents of an existing Lucene index and do other interesting stuff. I haven't used it myself, so I'm not sure, but I think it might help you in debugging this issue. Good luck!

I was able to solve my issue :
Index Writer must be created only once.You can check whether the index exits or not if not you create an new IndexWriter . for eg :
//The last parameter bool of an IndexWriter Contructor which says that you want to create an newIndexWriter or not
IndexWriter writer = new IndexWriter(GetFileInfo(indexName), analyzer, true);
On adding the new Document you must perform an check whether index exists or not , if it exists , then just pass bool param as false to the IndexWriter constructor:
IndexWriter writer = new IndexWriter(GetFileInfo(indexName), analyzer, false);
writer.AddDocument(CreateDocument(Id, text, dateTime));
writer.Optimize();
writer.Close();