.net ToString() format documentation

Question

I saw a code snippet the other day that converts a Boolean value to the corresponding \"Yes\"/\"No\" value:

CDbl(True).ToString(\"Yes;Yes;No\")

Answer 1

It's treating it as a Custom Numeric Format String. Specifically, see the part about section separators in the linked page:

The ';' character is used to separate sections for positive, negative, and zero numbers in the format string. If there are two sections in the custom format string, the leftmost section defines the formatting of positive and zero numbers, while the rightmost section defines the formatting of negative numbers. If there are three sections, the leftmost section defines the formatting of positive numbers, the middle section defines the formatting of negative numbers, and the rightmost section defines the formatting of zero numbers.