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如何在FxCop的自定义规则中获取传递给方法的参数值?

fxcop asp.net

2

Peter Alexandr Nikitin · 技术社区 · 14 年前

由于某些原因,在我们ASP.NETweb应用程序,不建议使用 Response.Redirect("something", True) . 对于 endResponse 参数。我们想用一个自定义的FxCop规则来实现这一点。我设法找到了响应。重定向,但现在我想找出争论。我该怎么做?

我们使用以下代码:

public override ProblemCollection Check(Member member)
{
    var method = member as Method;
    if (method != null)
    {
        foreach (var instruction in method.Instructions)
        {
            switch (instruction.OpCode)
            {
                case OpCode.Call:
                case OpCode.Callvirt:
                case OpCode.Newobj:
                    var call = (Method) instruction.Value;
                    if (call == null)
                    {
                        break;
                    }
                    if (call.Name.Name != "Redirect")
                    {
                        break;
                    }
                    if (call.Parameters.Count == 1)
                    {
                        //Redirect(url)
                        var resolution = GetResolution();
                        var problem = new Problem(resolution);
                        Problems.Add(problem);
                    }
                    if (call.Parameters.Count == 2)
                    {
                        VisitStatements(call.Body.Statements);
                    }
                    break;
                default:
                    break;
            }
        }
    }

    return Problems;
}

public override void VisitExpression(Expression expression)
{
    var methodCall = expression as MethodCall;
    if (methodCall == null)
    {
        return;
    }

    foreach (var operand in methodCall.Operands)
    {
        if (operand.Type.Name.Name == "Int16" || operand.Type.Name.Name == "Int32" || operand.Type.Name.Name == "Int64")
        {
            var literal = operand as Literal;
            if (literal != null && literal.Value is int)
            {
                var literalValue = (int)literal.Value;
                if (literalValue == 1)
                {
                    var resolution = GetResolution();
                    var problem = new Problem(resolution);
                    Problems.Add(problem);
                }
            }
        }
    }
}

Introspector 我想 结束响应 参数在幕后是一个整数,但我不再那么确定了。不管怎么说,这里面好像没有布尔值 methodCall.Operands

有没有人遇到过类似的情况,需要检查传递给方法的参数的实际值?

1 回复 | 直到 14 年前

1

Nicole Calinoiu 14 年前

而参数类型实际上是系统.布尔,FxCop IL解析器将其视为整数。下面是该规则的简化版本(假设您希望非文本endResponse值触发规则冲突):

    public override ProblemCollection Check(Member member)
    {
        Method method = member as Method;
        if (method != null)
        {
            this.Visit(method.Body);
        }

        return this.Problems;
    }

    public override void VisitMethodCall(MethodCall call)
    {
        base.VisitMethodCall(call);

        Method targetMethod = (Method)((MemberBinding)call.Callee).BoundMember;
        if (targetMethod.DeclaringType.FullName.Equals("System.Web.HttpResponse", StringComparison.Ordinal) &&
            targetMethod.Name.Name.Equals("Redirect", StringComparison.Ordinal))
        {
            bool callIsAcceptable = false;

            if (targetMethod.Parameters.Count == 2)
            {
                Expression endResponseOperand = call.Operands[1];
                if (endResponseOperand.NodeType == NodeType.Literal)
                {
                    if ((int)((Literal)endResponseOperand).Value == 1)
                    {
                        callIsAcceptable = true;
                    }
                }
            }

            if (!callIsAcceptable)
            {
                this.Problems.Add(new Problem(this.GetResolution(), call));
            }
        }
    }