C# assign problem

why do the normal assign method not working in C#? Do I need special conversion to convert from Javascript to C# type in the following example..

Javascript Code

private var moveDirection = Vector3.zero;
moveDirection = Vector3(0, 0, Input.GetAxis("Vertical"));        
moveDirection = transform.TransformDirection(moveDirection);

C# Code

private Vector3 moveDirection= Vector3.zero;
moveDirection = Vector3(0, 0, Input.GetAxis("Vertical"));
moveDirection = transform.TransformDirection(moveDirection);

Compliing C# code always give the error...

Please any one solve this out for me

You need to instansiate the `Vector3` class using the `new` keyword.

Vector3 moveDirection = Vector3.zero; 
moveDirection = new Vector3(0, 0, Input.GetAxis("Vertical")); 
moveDirection = transform.TransformDirection(moveDirection);