> ## Documentation Index
> Fetch the complete documentation index at: https://ancplua.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# AL0029 - Use HasAttribute extension

> Replace GetAttributes().Any() patterns with the cleaner HasAttribute extension method

Source: [AL0029UseHasAttributeAnalyzer.cs](https://github.com/ANcpLua/ANcpLua.Analyzers/blob/main/src/ANcpLua.Analyzers/Analyzers/AL0029UseHasAttributeAnalyzer.cs)

## Description

The `GetAttributes().Any(a => ...)` pattern and `foreach` loops over `GetAttributes()` are verbose. ANcpLua.Roslyn.Utilities provides the `HasAttribute()` extension method for cleaner attribute checks.

## Bad Code

```csharp theme={null}
using Microsoft.CodeAnalysis;

// LINQ pattern - verbose
if (symbol.GetAttributes().Any(a =>
    a.AttributeClass?.Name == "ObsoleteAttribute"))
{
    // ...
}

// foreach pattern - even more verbose
foreach (var attr in symbol.GetAttributes())
{
    if (attr.AttributeClass?.Name == "SerializableAttribute")
    {
        // ...
        break;
    }
}
```

## Good Code

```csharp theme={null}
using ANcpLua.Roslyn.Utilities;

// Clean extension method
if (symbol.HasAttribute("ObsoleteAttribute"))
{
    // ...
}

// Or with full type name
if (symbol.HasAttribute("System.SerializableAttribute"))
{
    // ...
}
```

## Properties

* **Category**: Usage
* **Severity**: Info
* **Enabled by default**: True
* **Code fix available**: False

## Configuration

```editorconfig theme={null}
dotnet_diagnostic.AL0029.severity = suggestion
```

## Notes

The `HasAttribute()` extension method:

* Accepts attribute name with or without "Attribute" suffix
* Supports fully qualified type names
* More efficient than LINQ with `Any()`
* Works with any `ISymbol` that can have attributes