Web 服务不接受输入

Question

我正在开发一个简单的 .Net 4.0 网络服务。我创建了一种方法，它接受字符串输入。我在调试模式下运行项目，因此在浏览器中打开一个页面，我可以在其中输入输入并调用服务的方法。不幸的是，我收到以下错误：

System.Web.HttpRequestValidationException: A potentially dangerous Request.Form value was detected from the client (xmlData="<?xml version="1.0" ...").
   at System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection)
   at System.Web.HttpRequest.ValidateNameValueCollection(NameValueCollection nvc, RequestValidationSource requestCollection)
   at System.Web.HttpRequest.get_Form()
   at System.Web.Services.Protocols.HtmlFormParameterReader.Read(HttpRequest request)
   at System.Web.Services.Protocols.HttpServerProtocol.ReadParameters()
   at System.Web.Services.Protocols.WebServiceHandler.CoreProcessRequest()

我尝试添加

 <pages validateRequest="false" />

到 web.config。它不起作用。

我能做什么？

Answer 1

我找到了解决办法：

在 .Net 4 中，您必须在 下添加以下行：

 <httpRuntime requestValidationType="MyService.CustomRequestValidator" />

CustomRequestValidator 类是您必须自己添加的验证。然后简单地重写 bool IsValidRequestString() 方法并返回 true 以消除验证：

/// <summary>
/// Validates the input based on some custom rules
/// </summary>
public class CustomRequestValidator : RequestValidator
{
    /// <summary>
    /// Validates a string that contains HTTP request data.
    /// </summary>
    /// <param name="context">The context of the current request.</param>
    /// <param name="value">The HTTP request data to validate.</param>
    /// <param name="requestValidationSource">An enumeration that represents the source of request data that is being validated. The following are possible values for the enumeration:QueryStringForm CookiesFilesRawUrlPathPathInfoHeaders</param>
    /// <param name="collectionKey">The key in the request collection of the item to validate. This parameter is optional. This parameter is used if the data to validate is obtained from a collection. If the data to validate is not from a collection, <paramref name="collectionKey"/> can be null.</param>
    /// <param name="validationFailureIndex">When this method returns, indicates the zero-based starting point of the problematic or invalid text in the request collection. This parameter is passed uninitialized.</param>
    /// <returns>
    /// true if the string to be validated is valid; otherwise, false.
    /// </returns>
    protected override bool IsValidRequestString(HttpContext context, string value, RequestValidationSource requestValidationSource, string collectionKey, out int validationFailureIndex)
    {
        // Set a default value for the out parameter.
        validationFailureIndex = -1;

        return true;

        //    // All other HTTP input checks are left to the base ASP.NET implementation.
        //    return base.IsValidRequestString(
        //                                        context,
        //                                        value,
        //                                        requestValidationSource,
        //                                        collectionKey,
        //                                        out validationFailureIndex);            
    }
}

}