Currently in C#, we need to first declare a variable before we pass it as an out parameter to a method. You can use a var while declaration if you initialize them in the same line, but when you don't want to initialize explicitly, you must declare them, specifying the full type:
// predeclaration of 'out' variable was mandatory
int result; // or, var result = 0;
string value = "125";
int.TryParse(value, out result);
Console.WriteLine("The result is: " + result);
In C# 7.0, the out variables can be declared right at the point where they are passed as an out parameter to a method. You can now directly write int.TryParse(value, out int result); and get the value of the out parameter, to use it in the scope of the enclosing block:
static void Main(string[] args)
{
string...
