C ++ Join concatenates all elements of the object array

Join ()-concatenates each element of the object array, where the specified separator is used between each element

Parameters

Separator

Type: System. String
The string to be used as the separator.

 

Values

Type: System. Object []
An array containing the elements to be connected.

 

Return value

Type: System. String
A string composed of values elements, which are separated by the separator string.

 

Take the following example and use StringBuilder to concatenate a set of strings:

 

String [] parts = {"Apple", "Orange", "Banana", "Pear", "Peach "};

Var builder = new StringBuilder ();

For (int I = 0; I <parts. Length; I ++)
{
Builder. Append (parts [I]);

// Remove the last ','

If (I! = Parts. Length-1)
    {
Builder. Append (",");
    }
}

// The result is "Apple, Orange, Banana, Pear, Peach"

Var result = builder. ToString ();

 

 

String. Join () can be easily implemented:

 

String [] parts = {"Apple", "Orange", "Banana", "Pear", "Peach "};
Var result = string. Join (",", parts );

 

 

Many people do not realize that Join () can merge any types, such as int, DateTime, double, or other custom types!

When string. when Join () merges non-string values, it actually causes each element ToString (). that is to say, the ToString () definition of these elements meets your needs-although most asp tutorials. the types in the. net library already exist.

For example:

  

// Merge integer "1, 2, 3, 4, 5, 6, 7, 8, 9, 10"

Var numsFromOneToTen = string. Join (",", Enumerable. Range (1, 10 ));

// Merge values of different types => "1-3.1415927-9/16/2011 12:52:22"

Var variousObjects = string. Join ("-", new object [] {1, 3.1415927, DateTime. Now });

 

Finally, Join () obviously supports IEnumerable <T> and object [], string []:

 

String [] arr = {"one", "two", "three "};
Console. WriteLine (string. Join (",", arr ));

// In. net 4.0, you can list all values directly without generating arrays.
Var numsFromOneToTen = string. Join (",", "A", "B", "C", "D", "E ");

Var variousObjects = string. Join ("-", 1, 3.1415927, DateTime. Now );