编写StyleCop自定义规则教程（二）校验规则增加配置参数

上一篇教程编写StyleCop自定义规则教程（一）---编写中文备注的简单校验规则 中使用的例子是校验代码中所有属性，不区分Public、Internal等。本文沿用原有例子增加两个规则的属性(IncludePublic和InculdeInternal)，规则根据这两个属性的开关值，控制是否检查代码中访问权限是Public或Internal的代码。

在规则的xml文件中加入Properties节点

<Properties>
    <BooleanProperty
      Name="IncludePublic"
      DefaultValue="True"
      FriendlyName="包括Pulbic"
      Description="代码分析时检验Public属性"
    />
    <BooleanProperty
      Name="IncludeInternal"
      DefaultValue="True"
      FriendlyName="包括Internal"
      Description="代码分析时检验Internal属性"
    />    
  </Properties>

CsDocument 类重载了多个WalkDocument方法，上一篇教程使用的是

WalkDocument(CodeWalkerElementVisitor<object> elementCallback,object context); 最后一个参数传入了空值，本文需要传入属性校验的开关值。因此使用void WalkDocument<T>(CodeWalkerElementVisitor<T> elementCallback, T context)，定义一个结构体传入用户配置的值。

[StructLayout(LayoutKind.Sequential)]
        private struct AnalyzerSettings
        {
            public bool IncludePublic;
            public bool IncludeInternal;
        }

private AnalyzerSettings LoadSettings(CodeDocument document)
        {
            AnalyzerSettings result = new AnalyzerSettings();
            result.IncludeInternal = true;
            result.IncludePublic = true;

            if (document.Settings != null)
            {
                BooleanProperty addInSetting = document.Settings.GetAddInSetting(this, "IncludePublic") as BooleanProperty;
                if (addInSetting != null)
                {
                    result.IncludePublic = addInSetting.Value;
                }

                addInSetting = document.Settings.GetAddInSetting(this, "IncludeInternal") as BooleanProperty;
                if (addInSetting != null)
                {
                    result.IncludeInternal = addInSetting.Value;
                }
            }

            return result;
        }

修改规则子类必须重写的AnalyzeDocument方法

public override void AnalyzeDocument(CodeDocument document)
        {
            Param.RequireNotNull(document, "document");
            CsDocument document2 = (CsDocument)document;
            if ((document2.RootElement != null) && !document2.RootElement.Generated)
            {
                AnalyzerSettings settings = LoadSettings(document);

                document2.WalkDocument<AnalyzerSettings>(new CodeWalkerElementVisitor<AnalyzerSettings>(this.CheckDocumentationForElement), settings);
            }
        }

原有的CheckDocumentationForElement方法最后一个参数就是传入的配置值，方法根据代码节点的类型和访问权限进行校验

private bool CheckDocumentationForElement(CsElement element, CsElement parentElement, AnalyzerSettings settings)
        {
            if (base.Cancel)
            {
                return false;
            }

            if (!element.Generated)
            {
                if ((element.ElementType == ElementType.Property) &&
                ((settings.IncludePublic && element.AccessModifier == AccessModifierType.Public) ||
                   (settings.IncludeInternal && element.AccessModifier == AccessModifierType.Internal)))
                {
                    this.ParseHeader(element, element.Header, element.LineNumber, false);
                }
            }
            return true;
        }

 编译后将dll放到stylecop目录，在stylecop settings中选中新的规则，可以在右侧Detailed settings中看到规则的两个开关值。

代码： /Files/Byeah/WithSettingRule.zip