Helpwiz.DotNetHelpers 1.0.2

Helpwiz Dot Net Helpers

This package contains a set of miscellaneous helper functions used by Helpwiz. Helpwiz is a marketplace for domestic cleaners - we allow clients who want to find a cleaner for their houses to choose and book a cleaner in a simple, one-pass process. We provide this package to anyone who wants to use it. It has several useful Linq extensions:

Linq extensions for Enumerables

• ArgMin(t ⇒ t.value), returns the element of the enumeration corresponding to the minimum of the quantity selected.
• ArgMax(t ⇒ t.value), returns the element of the enumeration corresponding to the maximum of the quantity selected.
• Distinct(t ⇒ t.property), returns the set of distinct values of a sub-property of the enumerated elements.
• Except(elem1, elem2, ...), returns an enumeration without the specified single values excluded.
• Concat(elem1, elem2, ...), returns an enumeration with the specified single values appended.
• SkipLast(), skips the last element of the enumeration.
• FirstIndexOf(t ⇒ bool), returns the first index matching the predicate.
• LastIndexOf(t ⇒ bool), returns the last index matching the predicate.
• RemoveAt(index), returns an enumeration with the element at the specified index removed.
• ToReadOnlyListFast(), returns the input cast to a read only list if possible, or as a new IReadOnlyList if not.
• ToSet(), returns a HashSet<T> of the input.
• ToSet(IEqualityComparer<T>), returns a HashSet<T> of the input with the specified comparer.
• ZipExt(...), extends Zip() to allow three, four and five enumerations as input.
• ForeachExt(Action<T>), applies the given action to all elements of an enumeration.
• ForeachZip(IEnumerable<T>, IEnumerable<T2>, Action<T, T2>), applies the given action to pairs of elements chosen from the two source enumerations.
• ToObservableCollection(), returns an ObservableCollection<T> of the input.

Linq extensions for comparables

• MinOrDefault(), returns the minimum or the default IComparable<T> if not found.
• MinOrDefault(t ⇒ t.x), returns the minimum or the default IComparable<T> if not found.
• MaxOrDefault(), returns the maximum or the default IComparable<T> if not found.
• MaxOrDefault(t ⇒ t.x), returns the maximum or the default IComparable<T> if not found.

Linq extensions for value-typed Enumerables

• Closest(int / decimal / double), returns the value in the enumeration numerically closest to the value provided.
• FirstOrNull(t ⇒ bool), returns the first matching value type as a nullable, or null if not found.
• FirstIndexOfOrNull(t ⇒ bool), returns the first matching index as a nullable integer, or null if not found.
• LastIndexOfOrNull(t ⇒ bool), returns the last matching index as a nullable integer, or null if not found.
• MaxOrNull(t ⇒ t.x), returns the maximum t.x as a nullable or null if not found.

Linq extensions for IEnumerable<double>

• MeanRejectingOutliers(this IEnumerable<double>), returns a nullable double representing the mean, with all items over 1.8 standard deviations from the sample mean rejected. Null if it cannot be calculated.
• StandardDeviation(this IEnumerable<double>), returns a double representing the standard deviation of the samples, or throws an exception if empty.

String Parsing Extensions

• ParseDoubleInvariant(this string), attempts to parse the string as an invariant-culture nullable double, returns null if it cannot.
• ParseDecimal(this string), attempts to parse the string as a nullable decimal, returns null if it cannot.
• ParseInt(this string), attempts to parse the string as a nullable integer, returns null if it cannot.
• ParseBool(this string), attempts to parse the string as a nullable bool, returns null if it cannot.
• ParseGuid(this string), attempts to parse the string as a nullable Guid, returns null if it cannot.

WPF Helpers

• Delegate Command - an implementation of ICommand that can be created by casting directly from a method group.