Converts the value of objects to strings based on the formats specified and inserts them into another string.
Namespace:System Assembly:System.Runtime.dll
Each overload of the Format method uses the composite formatting feature to include zero-based indexed placeholders, called format items, in a composite format string. At run time, each format item is replaced with the string representation of the corresponding argument in a parameter list. If the value of the argument is null, the format item is replaced with String.Empty.
Example
class Program{
static void Main(string[] args){
int number = 123;
var s = string.Format("{0:0.00}", number);
System.Console.WriteLine(s);
Console.ReadLine();
}
}Output
123.00
The string interpolation feature is built on top of the composite formatting feature and provides a more readable and convenient syntax to include formatted expression results in a result string. To identify a string literal as an interpolated string, prepend it with the $ symbol. You can embed any valid C# expression that returns a value in an interpolated string.
In the following example, as soon as an expression is evaluated, its result is converted into a string and included in a result string:
Example 2
class Program {
static void Main(string[] args){
int number = 123;
var aNumberAsString = $"{number:0.00}";
System.Console.WriteLine(aNumberAsString);
Console.ReadLine();
}
}Output
123.00