C sharp example (#240)

* add C# example

examples/c-sharp/count/Makefile

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+
+.PHONY: publish-osx publish-win help clean
+
+help:
+	@echo "make publish-win|publish-osx|clean"
+
+publish-win:
+	dotnet publish -c Release -r win-x64 --self-contained true -o ./publish/win-x64
+	@echo "Remember to copy libzsv.dll into ./publish/win-x64"
+
+publish-osx:
+	dotnet publish -c Release -r osx-arm64 --self-contained true -o ./publish/osx-arm64
+	@echo "Remember to copy libzsv.dylib into ./publish/win-x64"
+
+clean:
+	rm -rf obj bin publish

examples/c-sharp/count/Program.cs

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+using System;
+using System.IO;
+using System.Runtime.InteropServices;
+
+class ZsvInterop {
+  private const string ZsvDll =
+#if WINDOWS || WIN32 || WIN64 || _WIN32 || __WIN32
+    "libzsv.dll";
+#elif __MACOS__ || MACOS || OSX
+    "libzsv.dylib";
+#else
+    "libzsv.so"; // Default or throw an error
+#endif
+
+  private const string CRT_LIB =
+#if WINDOWS
+    "msvcrt.dll";
+#else
+    "libc";
+#endif
+
+  [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+  public delegate void ZsvRowHandler(IntPtr parser);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern IntPtr zsv_new(IntPtr opts);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern void zsv_delete(IntPtr parser);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern void zsv_set_row_handler(IntPtr parser, ZsvRowHandler handler);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern void zsv_set_context(IntPtr parser, IntPtr context);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern void zsv_set_input(IntPtr parser, IntPtr file);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern int zsv_parse_more(IntPtr parser);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern void zsv_finish(IntPtr parser);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern UIntPtr zsv_cell_count(IntPtr parser);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern IntPtr zsv_get_cell_str(IntPtr parser, UIntPtr cellIndex);
+
+  [DllImport(ZsvDll, CallingConvention = CallingConvention.Cdecl)]
+  public static extern UIntPtr zsv_get_cell_len(IntPtr parser, UIntPtr cellIndex);
+
+  [DllImport(CRT_LIB, CallingConvention = CallingConvention.Cdecl)]
+  public static extern IntPtr fopen(string filename, string mode);
+
+  [DllImport(CRT_LIB, CallingConvention = CallingConvention.Cdecl)]
+  public static extern int fclose(IntPtr file);
+}
+
+class Program {
+  static int lineCount = 0;
+
+  static void OnRowParsed(IntPtr parser) {
+    lineCount++;
+
+    /** example code for printing the first cell of each row:
+
+    UIntPtr cellCount = ZsvInterop.zsv_cell_count(parser);
+    if (cellCount.ToUInt64() > 0) {
+
+      // Index of the first cell
+      UIntPtr cellIndex = new UIntPtr(0);
+
+      // Get the pointer to the cell string
+      IntPtr cellStrPtr = ZsvInterop.zsv_get_cell_str(parser, cellIndex);
+
+      // Get the length of the cell string
+      UIntPtr cellLen = ZsvInterop.zsv_get_cell_len(parser, cellIndex);
+
+      // Convert the cell data to a string
+      int length = (int)cellLen.ToUInt64();
+      string cellValue = string.Empty;
+
+      if (length > 0) {
+        byte[] buffer = new byte[length];
+        Marshal.Copy(cellStrPtr, buffer, 0, length);
+        cellValue = System.Text.Encoding.UTF8.GetString(buffer);
+      }
+
+      Console.WriteLine($"Row {lineCount}: {cellValue}");
+    }
+    **/
+  }
+
+  static void Main(string[] args) {
+    if (args.Length != 1) {
+      Console.WriteLine("Usage: count-cs <csv_file_path>");
+      return;
+    }
+
+    string csvFilePath = args[0];
+
+    if (!File.Exists(csvFilePath)) {
+      Console.WriteLine($"Error: File '{csvFilePath}' does not exist.");
+      return;
+    }
+
+    IntPtr parser = ZsvInterop.zsv_new(IntPtr.Zero);
+    if (parser == IntPtr.Zero) {
+      Console.WriteLine("Failed to create zsv parser.");
+      return;
+    }
+
+    ZsvInterop.ZsvRowHandler handler = new ZsvInterop.ZsvRowHandler(OnRowParsed);
+    ZsvInterop.zsv_set_row_handler(parser, handler);
+    ZsvInterop.zsv_set_context(parser, parser);
+
+    // Open the file using fopen
+    IntPtr file = ZsvInterop.fopen(csvFilePath, "r");
+    if (file == IntPtr.Zero) {
+      Console.WriteLine($"Error: Failed to open file '{csvFilePath}'.");
+      ZsvInterop.zsv_delete(parser);
+      return;
+    }
+
+    ZsvInterop.zsv_set_input(parser, file);
+
+    int result = 0;
+    while (result == 0) {
+      result = ZsvInterop.zsv_parse_more(parser);
+    }
+
+    ZsvInterop.zsv_finish(parser);
+    ZsvInterop.zsv_delete(parser);
+    ZsvInterop.fclose(file);
+
+    if (result != 2) // zsv_status_no_more_input
+    {
+      Console.WriteLine("Parsing failed: " + $"{result}");
+    } else {
+      Console.WriteLine($"{lineCount-1}");
+    }
+  }
+}

examples/c-sharp/count/count.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(RuntimeIdentifier)' == 'win-x64' Or '$(RuntimeIdentifier)' == 'win-x86'">
+    <DefineConstants>WINDOWS</DefineConstants>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(RuntimeIdentifier)' == 'osx-x64' Or '$(RuntimeIdentifier)' == 'osx-arm64'">
+    <DefineConstants>OSX</DefineConstants>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(RuntimeIdentifier)' == 'linux-x64' Or '$(RuntimeIdentifier)' == 'linux-arm64'">
+    <DefineConstants>LINUX</DefineConstants>
+  </PropertyGroup>
+</Project>
+