static void Main(string[] args)
{
#region MyFuncA intを渡す
int ans = MyFuncA(1);
Console.WriteLine(ans);
#endregion
#region MyFuncB char[]を渡す
MyFuncB(2, "call MyFuncB from C#");
#endregion
#region MyFuncC char[]を渡して操作させる
StringBuilder sb = new StringBuilder(256);
MyFuncC(3, sb);
//領域不足だとAccessViolationException
//MyFuncC(4, new StringBuilder(4));
#endregion
#region MyFuncD 構造体を渡す
//渡す構造体の初期化
var st = new SampleStruct()
{
index = 4,
name = "構造体サンプル",
data = new int[50],
};
st.data[0] = 10;
st.data[1] = 20;
st.data[2] = 30;
MyFuncD(st);
#endregion
#region MyFuncE 構造体を渡して操作させる
var pst = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(SampleStruct)));
try
{
MyFuncE(pst);
var st_rtn = (SampleStruct)Marshal.PtrToStructure(pst, typeof(SampleStruct));
Console.WriteLine($"index = {st_rtn.index}");
Console.WriteLine($"name = {st_rtn.name}");
Console.WriteLine(($"data = [{st_rtn.data[0]},{st_rtn.data[1]},{st_rtn.data[2]}]"));
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(e);
}
finally
{
//必ずメモリ解放
Marshal.FreeHGlobal(pst);
}
#region 参照型の参照渡し・・・正常終了するが値がセットされない
Console.WriteLine("MyFuncE(参照型を渡すパターン)");
SampleStructClass stc = new SampleStructClass();
MyFuncE(stc);
Console.WriteLine($"index = {stc.index}");
Console.WriteLine($"name = {stc.name}");
//Console.WriteLine($"data = {stc.data[0]}, {stc.data[1]}, {stc.data[2]}");
#endregion
#endregion
#region MyFuncF ポインタを含む構造体を渡す
var pst2 = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(SampleStruct2)));
try
{
MyFuncF(pst2);
var st2 = (SampleStruct2)Marshal.PtrToStructure(pst2, typeof(SampleStruct2));
for (var i = 0; i < st2.length; i++)
{
var v = Marshal.ReadInt64(st2.data, i * sizeof(double));
Console.WriteLine($"data[{i}] = {BitConverter.Int64BitsToDouble(v)}");
}
}catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(e);
}
finally
{
Marshal.FreeHGlobal(pst2);
}
#endregion
#region MyFuncG intのポインタを渡す
int g = 0;
Console.WriteLine(g);
MyFuncG(ref g);
#endregion
#region MyFuncH intのポインタのポインタを渡す
unsafe
{
int h = 0;
int * pt1 = &h;
int **pt2 = &pt1;
Console.WriteLine(**pt2);
MyFuncH(pt2);
}
#endregion
#region MyFuncI 構造体SampleStructのポインタのポインタを渡す
var pst3 = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(SampleStruct)));
try
{
MyFuncI(ref pst3);
var st_rtn = (SampleStruct)Marshal.PtrToStructure(pst3, typeof(SampleStruct));
Console.WriteLine($"index = {st_rtn.index}");
Console.WriteLine($"name = {st_rtn.name}");
Console.WriteLine(($"data = [{st_rtn.data[0]},{st_rtn.data[1]},{st_rtn.data[2]}]"));
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(e);
}
finally
{
//必ずメモリ解放
Marshal.FreeHGlobal(pst);
}
#endregion
Console.ReadKey();
}
private static extern void MyFuncE(SampleStructClass st); //参照型を渡すパターン：NG