Moved some commonly used extension methods to core project.

Author: xivk

OsmSharp.Common.props

@@ -3,7 +3,7 @@
 
   <!--- Package information, Version -->
   <PropertyGroup>
-    <PackageVersion>7.0.0-pre020</PackageVersion>
+    <PackageVersion>7.0.0-pre021</PackageVersion>
     <LangVersion>latest</LangVersion>
     <Company>Itinero BV</Company>
     <Authors>OsmSharp Contributors</Authors>

src/OsmSharp/Streams/IEnumerableExtensions.cs

@@ -0,0 +1,39 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Threading.Tasks;
+
+namespace OsmSharp.Streams;
+
+/// <summary>
+/// Extension methods to easily save/load OSM data.
+/// </summary>
+public static class IEnumerableExtensions
+{
+    /// <summary>
+    /// Creates a new file and write the data as an OSM-XML file.
+    /// </summary>
+    /// <param name="data">The data to write.</param>
+    /// <param name="file">The file to create.</param>
+    public static void CreateAsOsmFile(this IEnumerable<OsmGeo> data, string file)
+    {
+        using var stream = File.Create(file);
+        using var outputStream = new OsmSharp.Streams.XmlOsmStreamTarget(stream);
+        outputStream.RegisterSource(data);
+        outputStream.Pull();
+        outputStream.Flush();
+    }
+    
+    /// <summary>
+    /// Creates a new file and write the data as OSM-PBF file.
+    /// </summary>
+    /// <param name="data">The data to write.</param>
+    /// <param name="file">The file to create.</param>
+    public static void CreateAsOsmPbfFile(this IEnumerable<OsmGeo> data, string file)
+    {
+        using var stream = File.Create(file);
+        var outputStream = new OsmSharp.Streams.PBFOsmStreamTarget(stream);
+        outputStream.RegisterSource(data);
+        outputStream.Pull();
+        outputStream.Flush();
+    }
+}