Question

I’ve found this symbol {0}, what’s this symbol mean?

Answer 1

It’s most often used as part of a string formatting function, and means that the first argument in a (zero-based) list should replace it. For example:

var output = String.Format("{0},{1}", "Hello", "World") // Gives "Hello, World"

String formatting is a common element in data binding, so you will also often see it as part of binding expressions.