Convert connection string from VB to C#

Question

I am trying to convert the following in VB (which works fine):

DBConn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings(GlobalVariables.strConnection).ConnectionString

To C#:

DBConn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings(GlobalVariables.strConnection).ConnectionString;

However I get the following error in C#:

Non-invocable member 'ConfigurationManager.ConnectionStrings' cannot be used like a method.

What then would be the proper way to convert to C# ?

Answer 1

Since ConnectionStrings is a collection with an indexer you have to use [...] in C#

DBConn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings[GlobalVariables.strConnection].ConnectionString;

Here's the indexer you're using.

Answer 2

In both VB and C# we use ( ) around arguments to methods, and the ( after a word representing a method will cause the method to be run

---

In VB things that behave like arrays (arrays, lists, dictionaries etc) are indexed with the same ( )

Dim arr = "a b c".Split()
Dim b = arr(1) 

..but in c# we use [ ] for indexing

var arr = "a b c".Split();
var b = arr[1];

If you get "non invocable member cannot be used like a method" when converting VB to C#, check anywhere you've used ( ) that should be [ ]. An additional hint in VS2019+ is look at the color of the thing before the (; if it's a method it's yellow. Properties (that cannot be called) are white. Because ( is only ever used for method calling in c#, and not for indexing, it's a mistake to put it next to a white thing