christiannagel

            <GridView.GroupStyle>
                <GroupStyle>
                    <GroupStyle.HeaderTemplate>
                        <DataTemplate>
                            <Grid Margin="1,0,0,6">
                                <Button Foreground="{StaticResource ApplicationHeaderForegroundThemeBrush}"
                                    AutomationProperties.Name="Group Title"
                                    Click="Header_Click"
                                    Style="{StaticResource TextBlockButtonStyle}" >
                                        <StackPanel Orientation="Horizontal">

christiannagel

                       <DataTemplate>
                            <Grid Margin="1,0,0,6">
                                <Button Foreground="{StaticResource ApplicationHeaderForegroundThemeBrush}"
                                    AutomationProperties.Name="Group Title"
                                    Click="Header_Click"
                                    Style="{StaticResource TextBlockButtonStyle}" >
                                    <Grid>
                                        <Grid.RowDefinitions>
                                            <RowDefinition />
                                            <RowDefinition />

christiannagel

            <GridView.ItemsPanel>
                <ItemsPanelTemplate>
                    <ItemsWrapGrid GroupPadding="0,0,70,0" Background="BlueViolet" />
                </ItemsPanelTemplate>
            </GridView.ItemsPanel>

christiannagel

private static void UsingSimpleArrays()
{
    Console.WriteLine(nameof(UsingSimpleArrays));
    for (int i = 0; i < 20; i++)
    {
        LocalUseOfArray(i);
    }
    Console.WriteLine();
    Console.WriteLine();
}

christiannagel

private static void UsingSimpleArraysWithGC()
{
    Console.WriteLine(nameof(UsingSimpleArraysWithGC));
    for (int i = 0; i < 20; i++)
    {
        GC.Collect(0);
        LocalUseOfArray(i);
    }
    Console.WriteLine();
    Console.WriteLine();

christiannagel

private static void LocalUseOfSharedPool(int i)
{
    int[] arr = ArrayPool<int>.Shared.Rent(ARRAYSIZE);
    ShowAddress($"simple array {i}", arr);
    FillTheArray(arr);
    UseTheArray(arr);
    ArrayPool<int>.Shared.Return(arr);
}

christiannagel

unsafe private static void ShowAddress(string name, int[] item)
{
    fixed (int* addr = item)
    {
        Console.Write($"\t0x{(ulong)addr:X}");
    }
}

christiannagel

public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> predicate)
{
    if (source == null) throw new ArgumentNullException(nameof(source));
    if (predicate == null) throw new ArgumentNullException(nameof(predicate));

    foreach (T item in source)
    {
        if (predicate(item))
        {
            yield return item;

christiannagel

public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> predicate)
{
    if (source == null) throw new ArgumentNullException(nameof(source));
    if (predicate == null) throw new ArgumentNullException(nameof(predicate));

    return WhereImpl(source, predicate);
}

private static IEnumerable<T> WhereImpl<T>(IEnumerable<T> source, Func<T, bool> predicate)
{

christiannagel

string[] names = { "James", "Niki", "John", "Gerhard", "Jack" };
var q = names.Where(null);

foreach (var n in q)  // callstack position for exception
{
    Console.WriteLine(n);
}