Fixed VB code and syntax highlighting #1799
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Thanks for noticing the rather bizarre language identifier, @svick. Eventually, we're planning to break this up into standalone C# and VB topics, so could you especially add the separate C# and VB code blocks for PropertyChanged?.Invoke(e)? Thanks.
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| The last example demonstrates that the null-condition operators are short-circuiting. If one operation in a chain of conditional member access and index operation returns null, then the rest of the chain’s execution stops. Other operations with lower precedence in the expression continue. For example, `E` in the following always executes, and the `??` and `==` operations execute. | ||
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| ```vb-c# | ||
| ```csharp |
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@svick Can you add semicolons at the ends of the lines of C# code?
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Those are not valid C# statements, so semicolons don't make sense here. I think they are just supposed to be two separate expressions.
Do you think it would be clearer if they were expanded to statements? Something like:
var maybeE = A?.B?.C?[0] ?? E;
var equalsE = A?.B?.C?[0] == E;| @@ -57,21 +59,18 @@ A?.B?.C?[0] == E | |||
| var handler = this.PropertyChanged; | |||
| if (handler != null) | |||
| handler(…) | |||
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| The new way is much simpler: | ||
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| ```vb-c# | ||
| ```csharp | ||
| PropertyChanged?.Invoke(e) |
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Could you break this out into two separate code blocks (even though they're basically identical)?
PropertyChanged?.Invoke(e);PropertyChanged?.Invoke(e)| PropertyChanged?.Invoke(e) | ||
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| The new way is thread-safe because the compiler generates code to evaluate `PropertyChanged` one time only, keeping the result in temporary variable. |
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@rpetrusha Addressed your comments, except the one where I commented.
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| The last example demonstrates that the null-condition operators are short-circuiting. If one operation in a chain of conditional member access and index operation returns null, then the rest of the chain’s execution stops. Other operations with lower precedence in the expression continue. For example, `E` in the following always executes, and the `??` and `==` operations execute. | ||
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| ```vb-c# | ||
| ```csharp |
There was a problem hiding this comment.
Those are not valid C# statements, so semicolons don't make sense here. I think they are just supposed to be two separate expressions.
Do you think it would be clearer if they were expanded to statements? Something like:
var maybeE = A?.B?.C?[0] ?? E;
var equalsE = A?.B?.C?[0] == E;
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I think that we can leave them. |
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I noticed this bizarre identifier this morning when I opening issue #1797. It was even on MSDN: https://msdn.microsoft.com/en-us/library/9c7b2c8f-a785-44ca-836c-407bfb6d27f5! |
When reviewing #1796, I noticed that this article used the invalid language identifier
vb-c#. I fixed that by changing it tocsharpin one case and added a separate VB block in the second, because the code was not valid VB.While here, I also fixed other invalid VB code.