You can create an implicitly-typed array in which the type of the array instance is inferred from the elements specified in the array initializer. The rules for any implicitly-typed variable also apply to implicitly-typed arrays. For more information, see Implicitly Typed Local Variables (C# Programming Guide).

Implicitly-typed arrays are usually used in query expressions together with anonymous types and object and collection initializers.

The following examples show how to create an implicitly-typed array:

class ImplicitlyTypedArraySample
{
    static void Main()
    {
        var a = new[] { 1, 10, 100, 1000 }; // int[]
        var b = new[] { "hello", null, "world" }; // string[]

        // single-dimension jagged array
        var c = new[]   
        {  
            new[]{1,2,3,4},
            new[]{5,6,7,8}
        };

        // jagged array of strings
        var d = new[]   
        {
            new[]{"Luca", "Mads", "Luke", "Dinesh"},
            new[]{"Karen", "Suma", "Frances"}
        };
    }
}

In the previous example, notice that with implicitly-typed arrays, no square brackets are used on the left side of the initialization statement. Note also that jagged arrays are initialized by using new [] just like single-dimension arrays. Multidimensional implicitly-typed arrays are not supported.