ReSharper starts analyzing a code file as soon as you open it in the editor, all the way you edit it, until it is closed. All detected code issues are highlighted in the editor according to their severity levels. The map of the issues is also displayed on the marker bar in the right part of the editor window, where you can see instantly the status of the file and click the marks to navigate to specific code issues.
Design-time inspection features
To illustrate the design-time code inspection performed by ReSharper, consider the following code excerpt displayed in the editor:
In this rather simple example, we can see the following features of ReSharper code inspection:
Status indicator that helps you to see at once whether the current file has errors or warnings.
A fix popup that appears for non-imported types. It is enough to press Alt+Enter or click this popup and ReSharper will add the missing directive for all types in the file. For more information, see Import Missing Namespaces.
A low-priority code issue (in this case, a suggestion related to an unused public member) is greyed out.
A medium-priority code issue (in this case, a warning about a symbol name that does not fit with the naming style) is highlighted with a blue curly underline.
A marker corresponding to the suggestion issue (3) is displayed on the marker bar.
A marker corresponding to the error issue (8) is displayed on the marker bar.
An action indicator that appears to the left of the caret position if ReSharper has anything to suggest there.
A high-priority code issues (in this case, errors related to an unresolved symbol and an incorrect return type) are highlighted with red text and red curly underline.
A marker corresponding to the warning issue (4) is displayed on the marker bar.
The action list, which opens by pressing Alt+Enter or clicking the action indicator (7), contains a list of quick-fixes for the issue at the caret.
A short description of the issue at the caret appears in the status bar. You can also view descriptions of code issues by hovering the mouse over highlighted code or over the issue markers on the marker bar (5,6,9)
If the solution-wide analysis is enabled, ReSharper allows you to see even more code issues. In this example, it detects the unused public member (3) and notifies about errors in other files of your solution. You can click the solution-wide analysis icon to explore the detected issues.
To make missing function returns, missing breaks in switch statements, and disposed resources more noticeable, use Code analysis hints.
Toggle design-time inspection
By default, design-time code inspection is enabled in all supported languages. However, you can disable it everywhere or turn it off for specific files if needed. For more information on configuring code inspection, see Configure Code Inspection Settings.
Select ReSharper | Options from the main menu or press Alt+R O, then choose Code Inspection | Settings on the left.
Use the Enable code analysis checkbox to toggle the design-time code inspection.
Optionally, you can enable or disable design-time inspection features on this page:
Color identifiers
This option lets you enable or disable ReSharper syntax highlighting scheme. If it is selected, language identifiers are highlighted with colors as defined in Visual Studio options: Tools | Options | Environment | Fonts and Colors. The list of syntax identifiers provided by ReSharper is available in the Display items list, each name starting with ReSharper prefix.
Highlight color usages
Enables highlighting of color definitions in code. For more information, see Color Assistance.
Highlight special characters in string literals
Enables highlighting of correct and incorrect escape sequences in non-verbatim strings. For example: For more information, see Regular Expressions Assistance.
Highlight context exits
This option, enabled by default, tells ReSharper to highlight all places where the control flow can exit the current context. For example, for a method, it will highlight the return type of the method, all return, throw keywords, and so on when you set the caret to one of these identifiers For a loop, it will additionally highlight the loop keyword as well as all the break statements inside this loop. Note that if a method is not entirely visible in the editor, you can invoke the Navigate To Function Exits command on the method name to trigger another kind of highlighting, which will not disappear when your caret leaves the method name.
If necessary, you can select the Enable solution-wide analysis checkbox to enable the Solution-Wide Analysis.
Click Save in the Options dialog to apply the modifications and let ReSharper choose where to save them, or save the modifications to a specific settings layer using the Save To list. For more information, see Manage and Share ReSharper Settings.
Navigate code issues
If the design-time code inspection is enabled, you can easily navigate between all issues (except those with the hint severity level) detected in the current file.
Navigate to the next/previous code issue in the current file
Press F12 to go to the next code issue, or Shift+F12 to go to the previous code issue.
In the main menu, choose ReSharper | Inspect | Next Issue in File or ReSharper | Inspect | Previous Issue in File. .
Use the marker bar on the right side of the editor window: clicking on markers brings the caret to the corresponding issues; clicking on the status indicator on top of the marker bar brings the caret to the next issue in the file.
Right-click the status indicator and choose Go to Next/Previous Error/Warning/Suggestion— these commands will help you navigate between code issues of the highest severity level. So if there are errors, they only navigate between errors, as soon as all errors are fixed they navigate between warnings, and so on.
If you are only interested in errors in the current file, you can jump between them skipping issues with lower severity levels. Besides, if you enable the Solution-Wide Analysis, you can jump between errors in the entire solution. Note that names of the navigation commands in the ReSharper | Inspect menu change if the solution-wide analysis is on. Specifically, Next Error/Warning changes to Next Error/Warning in Solution and Previous Error/Warning becomes Previous Error/Warning in Solution.
Navigate to the next/previous error
Press Alt+F12 to go to the next error, or Shift+Alt+F12 to go to the previous error.
In the main menu, choose ReSharper | Inspect | Next Error/Warning or ReSharper | Inspect | Previous Error/Warning.
If the Solution-Wide Analysis is enabled and there are some errors, the number of errors is displayed in the right corner of the status bar. You can click this number to go to the next error in the solution.
Inspection options menu
Besides suggested fixes, for each configurable code inspection as well as for custom inspections, ReSharper shows the Inspection [name of inspection] sub-menu in the actions list, with the following items:
For the most controversial issues, there is the Why is ReSharper suggesting this? item that opens a Code Inspection Index page with detailed description of the corresponding inspection.
Find similar issues
You can not only fix a highlighted issue with a quick-fix, but also find and investigate all similar issues (all issues detected with the same code inspection) in the whole solution or smaller scope.
Find similar issues
Set the caret at a highlighted issue in the editor.
To find similar issues in the current file, choose Inspection [name of inspection] | Find similar issues in [filename] file.
To find similar issues in the current project or solution, expand the submenu and choose the desired scope:
If necessary, you can search for similar issues in any project or solution folder within your solution. To do so, choose Find similar issues in custom scope in the submenu. In the dialog that opens, type the name of the desired project or solution folder, and then click OK.
Integration with Visual Studio code inspection controls
Starting from version 2015, Visual Studio comes with its own code analysis engine (Roslyn) and provides its own light bulbs feature to perform quick actions including refactoring and fixing errors.
Visual Studio's quick actions often perform the same fixes as ReSharper's quick-fixes, context action, or refactorings. Therefore, for some errors you may have two similar suggestions from Visual Studio and from ReSharper. In the illustration below, you can see two bulbs both suggesting to remove redundant using directives:
To avoid this, ReSharper provides the Hide Visual Studio light bulb option on the Environment | Editor | Visual Studio Features page of ReSharper options. This option is enabled by default, so you will not see the duplicated bulbs unless you disable it.
If Visual Studio Light Bulb is suppressed, Visual Studio actions can be integrated into ReSharper's action list by selecting the Merge Visual Studio light bulb actions into ReSharper action indicator checkbox. If it is selected, ReSharper does the following for each Visual Studio's quick action:
If there is a similar ReSharper's quick-fix or context action, the Visual Studio's quick action is not displayed.
If there are no similar ReSharper's action, the Visual Studio's action becomes available in the ReSharper's action list. You can recognize Visual Studio's quick actions by the special icon .
If necessary, you can also disable Visual Studio's error highlighting in the editor, so that only code issues found by ReSharper are highlighted. To do so, select Hide Visual Studio squiggles on the Environment | Editor | Visual Studio Features page of ReSharper options.
sub-menu in the actions list, with the following items: ![Inspection [name of inspection] sub-menu](/help/img/dotnet/2020.2/code_inspection_menu.png "Inspection [name of inspection] sub-menu")
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