[csharp][netcore] Update type "String" to "string" for consistent type

[prajon84]

This PR is for removing inconsistent use of type "String" and "string" by updating "String" to "string"

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@Blackclaws @lucamazzanti @wing328 @shibayan @jfeltesse-mdsol

[wing328]

@prajon84 thanks for the PR. What about following the advise in this SO: https://stackoverflow.com/a/7077/677735 ?

As far as guidelines, it's generally recommended to use string any time you're referring to an object.

Likewise, I think it's generally recommended to use String if you need to refer specifically to the class.

[lucamazzanti]

Good PR, I also wanted to start removing coding style warnings and hints.
Personally I would have done the same thing. William's proposal is a further improvement.

Visual Studio changes everything like in your PR.

• https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/style-rules/ide0049

Resharper has two different hints:

• https://www.jetbrains.com/help/resharper/2021.1/BuiltInTypeReferenceStyle.html
• https://www.jetbrains.com/help/resharper/2021.1/BuiltInTypeReferenceStyleForMemberAccess.html

The default setup is the VS one, so it shows the hints also on the static cases like String.Format().

But if you setup on Resharper the second hint as CLR preference, then the fix applied on the entire project will exclude the static cases. But we need to apply that code syntax on the project itself. We can add an .editorconfig file in the solution to commit this code syntax preference . This is also useful for the furhter emprovements.
We can do that directly on that PR or on another one in the future, if you find that useful.

The .editorconfig content for that change will be this hint:

• https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/style-rules/ide0049#dotnet_style_predefined_type_for_member_access

[*]

# Microsoft .NET properties
dotnet_style_predefined_type_for_member_access = false:suggestion

Without the shared project setting, I will choose the vanilla version moving everything to string, otherwhise the green hints on the IDEs will still remain.

[prajon84]

@prajon84 thanks for the PR. What about following the advise in this SO: stackoverflow.com/a/7077/677735 ?

Seems like that was old guidance.

It appears that the guidance in this area may have changed, as StyleCop now enforces the use of the C# specific aliases.

[prajon84]

We can add an .editorconfig file in the solution to commit this code syntax preference . This is also useful for the furter emprovements.

Seems like it requires other file updates too to add .editorconfig way and which needs another PR (i guess).

[devhl-labs]

string is the way it is normally written. It's very odd to see String. I don't think we should set .editorconfig. We should just satisfy all the code hints in vanilla Visual Studio.

[wing328]

Can you please follow the instructions in the PR checklist item 3 to update the samples?

[prajon84]

@wing328: I have updated the samples for bin/configs/csharp-netcore* and pushed the commit. But, the ci/circleci:build and continuous-integration/appveyor/pr build are still failing. Any ideas?

[wing328]

Appveyor tests passed via https://ci.appveyor.com/project/WilliamCheng/openapi-generator/builds/39666876