नोट
इस पृष्ठ तक पहुंच के लिए प्राधिकरण की आवश्यकता होती है। आप साइन इन करने या निर्देशिकाएँ बदलने का प्रयास कर सकते हैं।
इस पृष्ठ तक पहुंच के लिए प्राधिकरण की आवश्यकता होती है। आप निर्देशिकाएँ बदलने का प्रयास कर सकते हैं।
| Property | Value |
|---|---|
| Rule ID | IDE0120 |
| Title | Simplify LINQ expression |
| Category | Style |
| Subcategory | Unnecessary code rules (expression-level preferences) |
| Applicable languages | C# and Visual Basic |
Overview
This rule flags overly complex LINQ expressions, specifically expressions that call Enumerable.Where<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>) followed by one of the following methods:
- Any<TSource>(IEnumerable<TSource>)
- Count<TSource>(IEnumerable<TSource>)
- First<TSource>(IEnumerable<TSource>)
- FirstOrDefault<TSource>(IEnumerable<TSource>)
- Last<TSource>(IEnumerable<TSource>)
- LastOrDefault<TSource>(IEnumerable<TSource>)
- Single<TSource>(IEnumerable<TSource>)
- SingleOrDefault<TSource>(IEnumerable<TSource>)
Such expressions can be simplified by removing the call to Where<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>) and instead calling an overload of Any(), Count(), First(), FirstOrDefault(), Last(), LastOrDefault(), Single, or SingleOrDefault() that accepts a predicate function to filter the elements.
Options
This rule has no associated code-style options.
Example
// Code with violations.
IEnumerable<string> words = new List<string> { "hello", "world", "!" };
var result = words.Where(x => x.Equals("hello")).Any();
// Fixed code.
IEnumerable<string> words = new List<string> { "hello", "world", "!" };
var result = words.Any(x => x.Equals("hello"));
Suppress a warning
If you want to suppress only a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.
#pragma warning disable IDE0120
// The code that's violating the rule is on this line.
#pragma warning restore IDE0120
To disable the rule for a file, folder, or project, set its severity to none in the configuration file.
[*.{cs,vb}]
dotnet_diagnostic.IDE0120.severity = none
To disable all of the code-style rules, set the severity for the category Style to none in the configuration file.
[*.{cs,vb}]
dotnet_analyzer_diagnostic.category-Style.severity = none
For more information, see How to suppress code analysis warnings.