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guide/english/csharp/string-interpolation/index.md

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+---
+title: String Interpolation
+---
+
+# String Interpolation
+
+In C#, typically to concatenate strings you would either use the “+” operator or composite formatting with a method such as String.Format. By composite formatting I am referring to a format string with indexed placeholders (format items) and a list of objects to be used in the placeholders.
+##
+```
+string message = "Hello " + firstName + " " + lastName + "!";
+
+string message2 = string.Format("Hello {0} {1}!", firstName, lastName);
+```
+With interpolated string expressions, you have a string with contained expressions that are replaced with the expressions’ results. You have to prefix your string literal with a dollar sign ($). The expressions you want included in the string are placed inline enclosed in curly braces. The above message would now look like this:
+##
+```
+string message = $"Hello {firstName} {lastName}!";
+```
+**Small Bit Of Useful Information**
+In string interpolation you have the ability to call functions, properties and ternary operators:
+
+```
+int a = 3;
+int b = 454;
+string result = $"{a}+{b} = {a+b}";
+```