Leadtools.Codecs Namespace > RasterCodecs Class > EnumTags Method : EnumTags(String,Int32) Method |
public void EnumTags( string fileName, int pageNumber )
'Declaration Public Overloads Sub EnumTags( _ ByVal fileName As String, _ ByVal pageNumber As Integer _ )
'Usage Dim instance As RasterCodecs Dim fileName As String Dim pageNumber As Integer instance.EnumTags(fileName, pageNumber)
public void EnumTags( string fileName, int pageNumber )
function Leadtools.Codecs.RasterCodecs.EnumTags(String,Int32)( fileName , pageNumber )
public: void EnumTags( String^ fileName, int pageNumber )
This method will fire the TagFound event for each tag found in the file.
Currently, only TIFF and Exif files contain tags.
For multipage TIFF files, you can enumerate the tags from a particular page. Specify the page number which has the tags to be enumerated.
This method enumerates the standard TIFF tags and the user tags. Standard TIFF tags are less than 32767. User TIFF tags are usually between 32768 and 65535.
To enumerate the tags stored in a stream, use EnumTags(Stream,Int32).
To read a tag value, use ReadTag(String,Int32,Int32) and to read all the tags in a file, use ReadTags(String,Int32).
For general information about TIFF tags, refer to Implementing TIFF Comments and Tags.
Do not attempt to use DeleteTag(String,Int32,Int32) to delete tags from inside the TagFound event. If you want to delete tags that you enumerate, use this event to add the tags to a list. Upon returning from EnumTags(String,Int32), you can delete all the tags from the list.
You can use TagsSupported to determine whether a certain file format supports tags.
Imports Leadtools Imports Leadtools.Codecs Imports Leadtools.ImageProcessing Imports Leadtools.ImageProcessing.Color Imports Leadtools.Drawing Private tagsFileName As String Private myTags As RasterCollection(Of RasterTagMetadata) Private Sub EnumTagsExample(ByVal srcFileName As String, ByVal destFileName As String) Dim codecs As RasterCodecs = New RasterCodecs() tagsFileName = srcFileName myTags = New RasterCollection(Of RasterTagMetadata)() AddHandler codecs.TagFound, AddressOf codecs_TagFound codecs.EnumTags(srcFileName, 1) RemoveHandler codecs.TagFound, AddressOf codecs_TagFound ' We read all the tags now, save them to the file Console.WriteLine("{0} tags read, saving them to the destination file", myTags.Count) codecs.WriteTags(destFileName, 1, myTags) ' Clean up codecs.Dispose() End Sub Private Sub codecs_TagFound(ByVal sender As Object, ByVal e As CodecsEnumTagsEventArgs) Console.WriteLine("Tag: Id={0}, Count={1}, Type={2}", e.Id, e.Count, e.MetadataType) ' Read this tag from the file and add it to our collection Dim codecs As RasterCodecs = TryCast(sender, RasterCodecs) Dim tag As RasterTagMetadata = codecs.ReadTag(tagsFileName, 1, e.Id) myTags.Add(tag) End Sub
using Leadtools; using Leadtools.Codecs; using Leadtools.ImageProcessing; using Leadtools.ImageProcessing.Color; string tagsFileName; RasterCollection<RasterTagMetadata> myTags; void EnumTagsExample(string srcFileName, string destFileName) { RasterCodecs codecs = new RasterCodecs(); tagsFileName = srcFileName; myTags = new RasterCollection<RasterTagMetadata>(); codecs.TagFound += new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); codecs.EnumTags(srcFileName, 1); codecs.TagFound -= new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); // We read all the tags now, save them to the file Console.WriteLine("{0} tags read, saving them to the destination file", myTags.Count); codecs.WriteTags(destFileName, 1, myTags); // Clean up codecs.Dispose(); } void codecs_TagFound(object sender, CodecsEnumTagsEventArgs e) { Console.WriteLine("Tag: Id={0}, Count={1}, Type={2}", e.Id, e.Count, e.MetadataType); // Read this tag from the file and add it to our collection RasterCodecs codecs = sender as RasterCodecs; RasterTagMetadata tag = codecs.ReadTag(tagsFileName, 1, e.Id); myTags.Add(tag); }
RasterCodecsExamples.prototype.EnumTagsExample_Runner = function ( ) { Tools.SetLicense ( ) ; with ( Leadtools ) { with ( Leadtools.Codecs ) { var srcImage; var codecs = new RasterCodecs(); var tifFileWithTags = "Assets\\3polars.tif"; // save a GEO TIFF file first, b/c the example needs one var destFileName = "WriteTags.tif"; return Tools.AppLocalFolder().createFileAsync(destFileName).then ( function ( saveFile ) { srcImage = RasterImage.create(100, 100, 24, 96, RasterColorHelper.black); return codecs.saveAsync(srcImage, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 24)}) .then ( function ( ) { srcImage.close(); codecs.close(); return EnumTagsExample(tifFileWithTags, destFileName); }); } } } var tagsFileName; var myTags; function EnumTagsExample(srcFileName, destFileName) { Tools.SetLicense(); with (Leadtools) { with (Leadtools.Codecs) { var codecs = new RasterCodecs(); Leadtools.RasterSupport.initialize(); codecs.eventsDispatchMode = Leadtools.LeadEventsDispatchMode.useCoreDispatcher; codecs.addEventListener("tagfound", codecs_TagFound); tagsFileName = srcFileName; myTags = new Array(); return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) { return codecs.enumTagsAsync(LeadStreamFactory.create(loadFile), 1) }) .then(function () { codecs.removeEventListener("tagfound", codecs_TagFound); // We read all the tags now, save them to the file console.info(myTags.length, " tags read, saving them to the destination file"); return Tools.AppLocalFolder().createFileAsync(destFileName, Windows.Storage.CreationCollisionOption.openIfExists) }) .then(function (saveFile) { return codecs.writeTagsAsync(LeadStreamFactory.create(saveFile), 1, myTags) }) .then(function () { // Clean up codecs.close(); }); } } } function codecs_TagFound(e) { console.info("Tag: Id=" + e.id + ", Count=" + e.count + " Type=", e.metadataType); // Read this tag from the file and add it to our collection var codecs = e.target; return Tools.AppInstallFolder().getFileAsync(tagsFileName).then(function (loadFile) { return codecs.readTagAsync(Leadtools.LeadStreamFactory.create(loadFile), 1, e.id) }) .then(function (tag) { myTags.push(tag); }); }
using Leadtools; using Leadtools.Codecs; using Leadtools.ImageProcessing; using Leadtools.ImageProcessing.Color; string tagsFileName; List<RasterTagMetadata> myTags; async Task EnumTagsExample(string srcFileName, string destFileName) { RasterCodecs codecs = new RasterCodecs(); try { tagsFileName = srcFileName; myTags = new List<RasterTagMetadata>(); StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName); codecs.TagFound += new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); await codecs.EnumTagsAsync(LeadStreamFactory.Create(loadFile), 1); codecs.TagFound -= new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); // We read all the tags now, save them to the file Debug.WriteLine("{0} tags read, saving them to the destination file", myTags.Count); StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(destFileName, CreationCollisionOption.OpenIfExists); await codecs.WriteTagsAsync(LeadStreamFactory.Create(saveFile), 1, myTags); } catch (Exception ex) { string error = ""; RasterException rasterException = RasterException.FromHResult(ex.HResult); if (rasterException != null) error = rasterException.Message; else error = ex.Message; Debug.WriteLine(error); Assert.Fail(error); } // Clean up codecs.Dispose(); } async void codecs_TagFound(object sender, CodecsEnumTagsEventArgs e) { Debug.WriteLine("Tag: Id={0}, Count={1}, Type={2}", e.Id, e.Count, e.MetadataType); // Read this tag from the file and add it to our collection RasterCodecs codecs = sender as RasterCodecs; StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(tagsFileName); RasterTagMetadata tag = await codecs.ReadTagAsync(LeadStreamFactory.Create(loadFile), 1, e.Id); myTags.Add(tag); }
using Leadtools; using Leadtools.Codecs; using Leadtools.Examples; using Leadtools.ImageProcessing; using Leadtools.ImageProcessing.Color; using Leadtools.Windows.Media; Stream tagsStream; RasterCollection<RasterTagMetadata> myTags; void EnumTagsExample(Stream inStreamTif, Stream outStreamTif) { RasterCodecs codecs = new RasterCodecs(); tagsStream = inStreamTif; myTags = new RasterCollection<RasterTagMetadata>(); codecs.TagFound += new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); codecs.EnumTags(inStreamTif, 1); codecs.TagFound -= new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); // We read all the tags now, save them to the file Debug.WriteLine("{0} tags read, saving them to the destination file", myTags.Count); codecs.WriteTags(outStreamTif, 1, myTags); } void codecs_TagFound(object sender, CodecsEnumTagsEventArgs e) { Debug.WriteLine("Tag: Id={0}, Count={1}, Type={2}", e.Id, e.Count, e.MetadataType); // Read this tag from the file and add it to our collection RasterCodecs codecs = sender as RasterCodecs; RasterTagMetadata tag = codecs.ReadTag(tagsStream, 1, e.Id); myTags.Add(tag); }
Imports Leadtools Imports Leadtools.Codecs Imports Leadtools.ImageProcessing Imports Leadtools.ImageProcessing.Color Imports Leadtools.Windows.Media Private tagsStream As Stream Private myTags As RasterCollection(Of RasterTagMetadata) Private Sub EnumTagsExample(ByVal inStreamTif As Stream, ByVal outStreamTif As Stream) Dim codecs As RasterCodecs = New RasterCodecs() tagsStream = inStreamTif myTags = New RasterCollection(Of RasterTagMetadata)() AddHandler codecs.TagFound, AddressOf codecs_TagFound codecs.EnumTags(inStreamTif, 1) RemoveHandler codecs.TagFound, AddressOf codecs_TagFound ' We read all the tags now, save them to the file Debug.WriteLine("{0} tags read, saving them to the destination file", myTags.Count) codecs.WriteTags(outStreamTif, 1, myTags) End Sub Private Sub codecs_TagFound(ByVal sender As Object, ByVal e As CodecsEnumTagsEventArgs) Debug.WriteLine("Tag: Id={0}, Count={1}, Type={2}", e.Id, e.Count, e.MetadataType) ' Read this tag from the file and add it to our collection Dim codecs As RasterCodecs = TryCast(sender, RasterCodecs) Dim tag As RasterTagMetadata = codecs.ReadTag(tagsStream, 1, e.Id) myTags.Add(tag) End Sub