String::Join<T> Method (String^, IEnumerable<T>^)
Concatenates the members of a collection, using the specified separator between each member.
Assembly: mscorlib (in mscorlib.dll)
public: generic<typename T> [ComVisibleAttribute(false)] static String^ Join( String^ separator, IEnumerable<T>^ values )
Parameters
- separator
-
Type:
System::String^
The string to use as a separator.separator is included in the returned string only if values has more than one element.
- values
-
Type:
System.Collections.Generic::IEnumerable<T>^
A collection that contains the objects to concatenate.
Return Value
Type: System::String^A string that consists of the members of values delimited by the separator string. If values has no members, the method returns String::Empty.
Type Parameters
- T
The type of the members of values.
| Exception | Condition |
|---|---|
| ArgumentNullException | values is null. |
If separator is null, an empty string (String::Empty) is used instead. If any member of values is null, an empty string is used instead.
Join<T>(String^, IEnumerable<T>^) is a convenience method that lets you concatenate each member of an IEnumerable<T> collection without first converting them to strings. The string representation of each object in the IEnumerable<T> collection is derived by calling that object's ToString method.
This method is particular useful with Language-Integrated Query (LINQ) query expressions. For example, the following code defines a very simple Animal class that contains the name of an animal and the order to which it belongs. It then defines a List<T> object that contains a number of Animal objects. The Enumerable::Where<TSource> extension method is called to extract the Animal objects whose Order property equals "Rodent". The result is passed to the Join<T>(String^, IEnumerable<T>^) method.
The following example uses the Sieve of Eratosthenes algorithm to calculate the prime numbers that are less than or equal to 100. It assigns the result to a List<T> object of type integer, which it then passes to the Join<T>(String^, IEnumerable<T>^) method.
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 4.0
Windows Phone Silverlight
Available since 7.1
Windows Phone
Available since 8.1