join two strings in csharp

main.cs
string str1 = "Hello";
string str2 = "World";
string result = str1 + " " + str2; //result: "Hello World"
105 chars
4 lines

main.cs
string str1 = "Hello";
string str2 = "World";
string result = string.Concat(str1, " ", str2); //result: "Hello World"
118 chars
4 lines

main.cs
string str1 = "Hello";
string str2 = "World";
string[] strArray = { str1, str2 };
string result = string.Join(" ", strArray); //result: "Hello World"
150 chars
5 lines