Develop Reference

Lucene.Net (4.8) AutoComplete / AutoSuggestion

I'd like to implement a searchable index using Lucene.Net 4.8 that supplies a user with suggestions / autocomplete for single words & phrases.
The index has been created successfully; the suggestions are where I've stalled.
Version 4.8 seems to have introduced a substantial number of breaking changes, and none of the available samples I've found work.
Where I stand
For reference, LuceneVersion is this:
private readonly LuceneVersion LuceneVersion = LuceneVersion.LUCENE_48;
Solution 1
I've tried this, but can't get past reader.Terms:
public void TryAutoComplete()
{
var analyzer = new EnglishAnalyzer(LuceneVersion);
var config = new IndexWriterConfig(LuceneVersion, analyzer);
RAMDirectory dir = new RAMDirectory();
using (IndexWriter iw = new IndexWriter(dir, config))
{
Document d = new Document();
TextField f = new TextField("text","",Field.Store.YES);
d.Add(f);
f.SetStringValue("abc");
iw.AddDocument(d);
f.SetStringValue("colorado");
iw.AddDocument(d);
f.SetStringValue("coloring book");
iw.AddDocument(d);
iw.Commit();
using (IndexReader reader = iw.GetReader(false))
{
TermEnum terms = reader.Terms(new Term("text", "co"));
int maxSuggestsCpt = 0;
// will print:
// colorado
// coloring book
do
{
Console.WriteLine(terms.Term.Text);
maxSuggestsCpt++;
if (maxSuggestsCpt >= 5)
break;
}
while (terms.Next() && terms.Term.Text.StartsWith("co"));
}
}
}
reader.Terms no longer exists. Being new to Lucene, it's unclear how to refactor this.
Solution 2
Trying this, I'm thrown an error:
public void TryAutoComplete2()
{
using(var analyzer = new EnglishAnalyzer(LuceneVersion))
{
IndexWriterConfig config = new IndexWriterConfig(LuceneVersion, analyzer);
RAMDirectory dir = new RAMDirectory();
using(var iw = new IndexWriter(dir,config))
{
Document d = new Document()
{
new TextField("text", "this is a document with a some words",Field.Store.YES),
new Int32Field("id", 42, Field.Store.YES)
};
iw.AddDocument(d);
iw.Commit();
using (IndexReader reader = iw.GetReader(false))
using (SpellChecker speller = new SpellChecker(new RAMDirectory()))
{
//ERROR HERE!!!
speller.IndexDictionary(new LuceneDictionary(reader, "text"), config, false);
string[] suggestions = speller.SuggestSimilar("dcument", 5);
IndexSearcher searcher = new IndexSearcher(reader);
foreach (string suggestion in suggestions)
{
TopDocs docs = searcher.Search(new TermQuery(new Term("text", suggestion)), null, Int32.MaxValue);
foreach (var doc in docs.ScoreDocs)
{
System.Diagnostics.Debug.WriteLine(searcher.Doc(doc.Doc).Get("id"));
}
}
}
}
}
}
When debugging, speller.IndexDictionary(new LuceneDictionary(reader, "text"), config, false); throws a The object cannot be set twice! error, which I can't explain.
Any thoughts are welcome.
Clarification
I'd like to return a list of suggested terms for a given input, not the documents or their full content.
For example, if a document contains "Hello, my name is Clark. I'm from Atlanta," and I submit "Atl," then "Atlanta" should come back as a suggestion.

If I am understanding you correctly you may be over-complicating your index design a bit. If your goal is to use Lucene for auto-complete, you want to create an index of the terms you consider complete. Then simply query the index using a PrefixQuery using a partial word or phrase.
using Lucene.Net.Analysis;
using Lucene.Net.Analysis.En;
using Lucene.Net.Documents;
using Lucene.Net.Index;
using Lucene.Net.Search;
using Lucene.Net.Store;
using Lucene.Net.Util;
using System;
using System.Linq;
namespace LuceneDemoApp
{
class LuceneAutoCompleteIndex : IDisposable
{
const LuceneVersion Version = LuceneVersion.LUCENE_48;
RAMDirectory Directory;
Analyzer Analyzer;
IndexWriterConfig WriterConfig;
private void IndexDoc(IndexWriter writer, string term)
{
Document doc = new Document();
doc.Add(new StringField(FieldName, term, Field.Store.YES));
writer.AddDocument(doc);
}
public LuceneAutoCompleteIndex(string fieldName, int maxResults)
{
FieldName = fieldName;
MaxResults = maxResults;
Directory = new RAMDirectory();
Analyzer = new EnglishAnalyzer(Version);
WriterConfig = new IndexWriterConfig(Version, Analyzer);
WriterConfig.OpenMode = OpenMode.CREATE_OR_APPEND;
}
public string FieldName { get; }
public int MaxResults { get; set; }
public void Add(string term)
{
using (var writer = new IndexWriter(Directory, WriterConfig))
{
IndexDoc(writer, term);
}
}
public void AddRange(string[] terms)
{
using (var writer = new IndexWriter(Directory, WriterConfig))
{
foreach (string term in terms)
{
IndexDoc(writer, term);
}
}
}
public string[] WhereStartsWith(string term)
{
using (var reader = DirectoryReader.Open(Directory))
{
IndexSearcher searcher = new IndexSearcher(reader);
var query = new PrefixQuery(new Term(FieldName, term));
TopDocs foundDocs = searcher.Search(query, MaxResults);
var matches = foundDocs.ScoreDocs
.Select(scoreDoc => searcher.Doc(scoreDoc.Doc).Get(FieldName))
.ToArray();
return matches;
}
}
public void Dispose()
{
Directory.Dispose();
Analyzer.Dispose();
}
}
}
Running this:
var indexValues = new string[] { "apple fruit", "appricot", "ape", "avacado", "banana", "pear" };
var index = new LuceneAutoCompleteIndex("fn", 10);
index.AddRange(indexValues);
var matches = index.WhereStartsWith("app");
foreach (var match in matches)
{
Console.WriteLine(match);
}
You get this:
apple fruit
appricot

C# (Xamarin iOS) How to loop son data on Custom UITableViewCell?

Any Help will be appreaciated :) Thank you in advance
I tried to loop other object inside of the function and its working but on this, it can't loop. Help. this is rush, and I'm not that familiar with creating iOS app.
public override void ViewDidLoad()
{
base.ViewDidLoad();
using (var web = new WebClient())
{
var url = "http://www.creativeinterlace.com/smitten/maintenance/api/feeds/get-miss-location/101";
json = web.DownloadString(url);
}
json = json.Replace("{\"location\":", "").Replace("}]}", "}]");
var ls = JArray.Parse(json);
if (ls.Count != 0)
{
foreach (var x in ls)
{
var name = x.SelectToken("location");
name1 = Convert.ToString(name);
var loc = x.SelectToken("address");
loc1 = Convert.ToString(loc);
var time = x.SelectToken("time_ago");
time1 = Convert.ToString(time);
locations = new List<Locations>
{
new Locations
{
shopname = name1,
address= loc1,
time = time1
},
};
}
nmtable.Source = new LocationSource(locations);
nmtable.RowHeight = 60;
nmtable.ReloadData();
}
}

You initialize the locations every time in the loop,so the list updates with only the newest object. You should initialize the list outside of the loop , and add object every time.
locations = new List<Locations>();
if (ls.Count != 0)
{
foreach (var x in ls)
{
var name = x.SelectToken("location");
name1 = Convert.ToString(name);
var loc = x.SelectToken("address");
loc1 = Convert.ToString(loc);
var time = x.SelectToken("time_ago");
time1 = Convert.ToString(time);
locations.Add(new Locations{ shopname = name1,address= loc1,time = time1});
};
}

How to determine the coordinatesystem of a shapefile set with ShapefileDataReader

I have the following code to read a shapefile set (.dbf, .prj, .shp, .shx) with the NetTopologySuite.IO.ShapefileDataReader:
public FeatureCollection ReadShapeFile(string localShapeFile)
{
var collection = new FeatureCollection();
var factory = new GeometryFactory();
using (var reader = new ShapefileDataReader(localShapeFile, factory))
{
var header = reader.DbaseHeader;
while (reader.Read())
{
var f = new Feature {Geometry = reader.Geometry};
var attrs = new AttributesTable();
for (var i = 0; i < header.NumFields; i++)
{
attrs.AddAttribute(header.Fields[i].Name, reader.GetValue(i));
}
f.Attributes = attrs;
collection.Add(f);
}
}
return collection;
}
This works, but the geometry objects don't have a property to tell which reference system the coordinates are in.
How can I find out which coordinate system / reference system the shape file or individual shapes are in?

The projection is not available in the .shp file, but in the .prj file, and can be loaded separately:
var projectionFile = Path.Combine(Path.GetDirectoryName(localShapeFile), Path.GetFileNameWithoutExtension(localShapeFile) + ".prj");
var projectionInfo = ProjectionInfo.Open(projectionFile);

UPS API - LabelLinksIndicator - Object Reference not set to an instance of an object

Below is some code for generating a UPS shipping label. It is based on the .net sample provided in the UPS developer kit. My problem is with the line highlighted in bold below. It throws and error as follows "System.NullReferenceException: Object reference not set to an instance of an object.".
What I know is this LabelLinksIndicator is required if you want the UPS API to return a link to a label. Otherwise it returns details on the shipment but no label. The relevant section of the UPS documentation is at the bottom of my question.
What do I need to do to overcome this error? It is not clear to me from the documentation what value I should be passing for LabelLinksIndicator. I've tried passing a 1, true and and an empty string. Same error in every case. The error message seems to indicate that there is an object I need to instantiate that I am not currently. However, I can't figure out what to instantiate. The available information on the web and on UPS.com is unfortunately sparse.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Foo.Web.UPSWebReference;
namespace Foo.Web.Auth
{
public partial class UPS : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (Request.QueryString["id"] != null)
{
try
{
ShipService shpSvc = new ShipService();
ShipmentRequest shipmentRequest = new ShipmentRequest();
UPSSecurity upss = new UPSSecurity();
UPSSecurityServiceAccessToken upssSvcAccessToken = new UPSSecurityServiceAccessToken();
upssSvcAccessToken.AccessLicenseNumber = "foo";
upss.ServiceAccessToken = upssSvcAccessToken;
UPSSecurityUsernameToken upssUsrNameToken = new UPSSecurityUsernameToken();
upssUsrNameToken.Username = "foo";
upssUsrNameToken.Password = "foo";
upss.UsernameToken = upssUsrNameToken;
shpSvc.UPSSecurityValue = upss;
RequestType request = new RequestType();
String[] requestOption = { "nonvalidate" };
request.RequestOption = requestOption;
shipmentRequest.Request = request;
ShipmentType shipment = new ShipmentType();
shipment.Description = "Ship webservice example";
ReturnServiceType rtn = new ReturnServiceType();
rtn.Code = "8";
rtn.Description = "Description";
ShipperType shipper = new ShipperType();
shipper.ShipperNumber = "foo";
PaymentInfoType paymentInfo = new PaymentInfoType();
ShipmentChargeType shpmentCharge = new ShipmentChargeType();
BillShipperType billShipper = new BillShipperType();
billShipper.AccountNumber = "foo";
shpmentCharge.BillShipper = billShipper;
shpmentCharge.Type = "01";
ShipmentChargeType[] shpmentChargeArray = { shpmentCharge };
paymentInfo.ShipmentCharge = shpmentChargeArray;
shipment.PaymentInformation = paymentInfo;
foo.Web.UPSWebReference.ShipAddressType shipperAddress = new foo.Web.UPSWebReference.ShipAddressType();
String[] addressLine = { "301 166th Street" };
shipperAddress.AddressLine = addressLine;
shipperAddress.City = "Jersey City";
shipperAddress.PostalCode = "07310";
shipperAddress.StateProvinceCode = "NJ";
shipperAddress.CountryCode = "US";
shipperAddress.AddressLine = addressLine;
shipper.Address = shipperAddress;
shipper.Name = "ABC Associates";
shipper.AttentionName = "ABC Associates";
ShipPhoneType shipperPhone = new ShipPhoneType();
shipperPhone.Number = "1234567890";
shipper.Phone = shipperPhone;
shipment.Shipper = shipper;
ShipFromType shipFrom = new ShipFromType();
foo.Web.UPSWebReference.ShipAddressType shipFromAddress = new foo.Web.UPSWebReference.ShipAddressType();
String[] shipFromAddressLine = { "100 82nd Street" };
shipFromAddress.AddressLine = addressLine;
shipFromAddress.City = "New York";
shipFromAddress.PostalCode = "10024";
shipFromAddress.StateProvinceCode = "NY";
shipFromAddress.CountryCode = "US";
shipFrom.Address = shipFromAddress;
shipFrom.AttentionName = "Mr.ABC";
shipFrom.Name = "ABC Associates";
shipment.ShipFrom = shipFrom;
ShipToType shipTo = new ShipToType();
ShipToAddressType shipToAddress = new ShipToAddressType();
String[] addressLine1 = { "Some Street" };
shipToAddress.AddressLine = addressLine1;
shipToAddress.City = "Roswell";
shipToAddress.PostalCode = "30076";
shipToAddress.StateProvinceCode = "GA";
shipToAddress.CountryCode = "US";
shipTo.Address = shipToAddress;
shipTo.Address.ResidentialAddressIndicator = "1"; //dan
shipTo.AttentionName = "DEF";
shipTo.Name = "DEF Associates";
ShipPhoneType shipToPhone = new ShipPhoneType();
shipToPhone.Number = "1234567890";
shipTo.Phone = shipToPhone;
shipment.ShipTo = shipTo;
ServiceType service = new ServiceType();
service.Code = "03";
service.Description = "Ground";
shipment.Service = service;
PackageType package = new PackageType();
package.Description = "Deliver to Warehouse";
PackageWeightType packageWeight = new PackageWeightType();
packageWeight.Weight = "10";
ShipUnitOfMeasurementType uom = new ShipUnitOfMeasurementType();
uom.Code = "LBS";
packageWeight.UnitOfMeasurement = uom;
package.PackageWeight = packageWeight;
PackagingType packType = new PackagingType();
packType.Code = "02";
package.Packaging = packType;
PackageType[] pkgArray = { package };
shipment.Package = pkgArray;
LabelSpecificationType labelSpec = new LabelSpecificationType();
LabelImageFormatType labelImageFormat = new LabelImageFormatType();
labelImageFormat.Code = "GIF";
labelSpec.LabelImageFormat = labelImageFormat;
string userAgent = Request.UserAgent;
labelSpec.HTTPUserAgent = userAgent;
shipmentRequest.LabelSpecification = labelSpec;
**shipmentRequest.Shipment.ShipmentServiceOptions.LabelDelivery.LabelLinksIndicator = "1";**
shipmentRequest.Shipment = shipment;
System.Net.ServicePointManager.CertificatePolicy = new TrustAllCertificatePolicy();
ShipmentResponse shipmentResponse = shpSvc.ProcessShipment(shipmentRequest);
Response.Redirect(shipmentResponse.ShipmentResults.LabelURL.ToString());

I figured out what the problem was. I needed first to new-up an instance of
ShipmentTypeShipmentServiceOptions shipServOpt = new ShipmentTypeServiceOptions();
and
LabelDeliveryType labelDel = new LabelDeliveryType();
Then set the LabelLinksIndicator element
labeldel.LabelLinksIndicator = "";
Then assign the options to my shipment instance
shipment.ShipmentServiceOptions = shipServOpt;
Note, ShipmentServiceOptionsType is NOT the same as ShipmentTypeServiceOptions. This tripped me up for a while.
Dear UPS, if you are reading this please consider improving upon your documentation and providing a more complete set of code examples.

shipmentRequest.Shipment appears to be null, since you aren't assigning anything to it until the next line. So, you can't do shipmentRequest.Shipment.ANYTHING. Switch them around, so that you have
shipmentRequest.Shipment = shipment;
shipmentRequest.Shipment.ShipmentServiceOptions.LabelDelivery.LabelLinksIndicator = "1";

The element needs to get passed as <LabelLinksIndicator/> in the XML. In your sample you'd be sending it as <LabelLinksIndicator>1</LabelLinksIndicator> which is invalid.

Reading the XML values using LINQ

what is the best way of reading xml file using linq and the below code you will see that, I have three different loops and I feel like its not elegant or do I have options to retrofit the below code?
public static void readXMLOutput(Stream stream)
{
XDocument xml = new XDocument();
xml = LoadFromStream(stream);
var header = from p in xml.Elements("App").Elements("Application")
select p;
foreach (var record in header)
{
string noym = record.Element("nomy").Value;
string Description = record.Element("Description").Value;
string Name = record.Element("Name").Value;
string Code = record.Element("Code").Value;
}
var appRoles = from q in xml.Elements("App").Elements("Application").Elements("AppRoles").Elements("Role")
select q;
foreach (var record1 in appRoles)
{
string Name = record1.Element("Name").Value;
string modifiedName = record1.Element("ModifiedName").Value;
}
var memeber = from r in xml.Elements("App").Elements("Application").Elements("AppRoles").Elements("Role").Elements("Members")
select r;
foreach (var record2 in memeber)
{
string ExpirationDate = record2.Element("ExpirationDate").Value;
string FullName = record2.Element("FullName").Value;
}
}
UPDATED:
foreach (var record in headers)
{
..............
string Name1 = record.Attribute("Name").Value;
string UnmodifiedName = record.Attribute("UnmodifiedName").Value;
string ExpirationDate = record.Attribute("ExpirationDate").Value;
string FullName = record.Attribute("FullName").Value;
...............
}

Is that your actual code ? All those string variables you are assigning in the foreach loops only have a scope of one iteration of the loop. They are created and destroyed each time.

This may not work precisely in your case depending on the xml structure. Play around with it. Try it using LinqPad
var applications = from p in xml.Descendants("Application")
select new { Nomy = p.Element("nomy").Value
, Description = p.Element("Description").Value
, Name = p.Element("Name").Value
, Code = p.Element("Code").Value
};
var appRoles = from r in xml.Descendants("Role")
select new { Name = r.Element("Name").Value
, ModifiedName = r.Element("ModifiedName").Value
};

This answer is a hierarchical query.
var headers =
from header in xml.Elements("App").Elements("Application")
select new XElement("Header",
new XAttribute("noym", header.Element("nomy").Value),
new XAttribute("Description", header.Element("Description").Value),
new XAttribute("Name", header.Element("Name").Value),
new XAttribute("Code", header.Element("Code").Value),
from role in header.Elements("AppRoles").Elements("Role")
select new XElement("Role",
new XAttribute("Name", role.Element("Name").Value),
new XAttribute("ModifiedName", role.Element("ModifiedName").Value),
from member in role.Elements("Members")
select new XElement("Member",
new XAttribute("ExpirationDate", member.Element("ExpirationDate").Value),
new XAttribute("FullName", member.Element("FullName").Value)
)
)
);