String.Join Method (String, IEnumerable(String))
Concatenates the members of a constructed IEnumerable(T) collection of type String, using the specified separator between each member.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
[<ComVisibleAttribute(false)>] static member Join : separator:string * values:IEnumerable<string> -> string
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(String)
A collection that contains the strings to concatenate.
Return Value
Type: System.StringA string that consists of the members of values delimited by the separator string. If values has no members, the method returns String.Empty.
| Exception | Condition |
|---|---|
| ArgumentNullException | values is a null reference (Nothing in Visual Basic). |
If separator is a null reference (Nothing in Visual Basic), an empty string (String.Empty) is used instead. If any member of values is a null reference (Nothing in Visual Basic), an empty string is used instead.
Join(String, IEnumerable(String)) is a convenience method that lets you concatenate each element in an IEnumerable(Of String) collection without first converting the elements to a string array. It is particularly useful with Language-Integrated Query (LINQ) query expressions. The following example passes a List(Of String) object that contains either the uppercase or lowercase letters of the alphabet to a lambda expression that selects letters that are equal to or greater than a particular letter (which, in the example, is "M"). The IEnumerable(Of String) collection returned by the Enumerable.Where method is passed to the Join(String, IEnumerable(String)) method to display the result as a single string.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
