XML 解析到对象，得到无效的操作异常

Question

我尝试为 Flurl 添加扩展方法，将 http 响应从 xml 解析到对象。 有代码

 public static async Task<T> ReceiveXml<T>(this Task<IFlurlResponse> content)
    {
        var response = await content.ConfigureAwait(false);
        if (response == null) return default(T);
        try
        {
            var originData = await response.GetStreamAsync().ConfigureAwait(false);
            var serializer = new XmlSerializer(typeof(T));
            var result = (T)serializer.Deserialize(originData);
            return result;
        }
        catch (Exception)
        {
            response.Dispose();
            throw;
        }
    }

但是当我试图解析这个 xml 时

<Service.ABC
xmlns="http://schemas.datacontract.org/2004/07/Services.Public"
xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<Amount>0</Amount>
<CustomerID i:nil="true"/>
<ID>0</ID>
<UpdatedDate i:nil="true"/>
</Service.ABC>

我收到了一个错误

System.InvalidOperationException: 不是预期的。

我建立的模型来自

https://json2csharp.com/xml-to-csharp

[XmlRoot(ElementName="CustomerID")]
public class CustomerID { 

    [XmlAttribute(AttributeName="nil")] 
    public bool Nil { get; set; } 
}

[XmlRoot(ElementName="UpdatedDate")]
public class UpdatedDate { 

    [XmlAttribute(AttributeName="nil")] 
    public bool Nil { get; set; } 
}

[XmlRoot(ElementName="Service.ABC")]
public class ServiceABC { 

    [XmlElement(ElementName="Amount")] 
    public int Amount { get; set; } 

    [XmlElement(ElementName="CustomerID")] 
    public CustomerID CustomerID { get; set; } 

    [XmlElement(ElementName="ID")] 
    public int ID { get; set; } 

    [XmlElement(ElementName="UpdatedDate")] 
    public UpdatedDate UpdatedDate { get; set; } 

    [XmlAttribute(AttributeName="xmlns")] 
    public string Xmlns { get; set; } 

    [XmlAttribute(AttributeName="i")] 
    public string I { get; set; } 

    [XmlText] 
    public int Text { get; set; } 
}

如果使用 XmlDocument 并加载此 xml 文件可以成功解析，所以...我认为该文件是正确的。 但是 XmlSerializer 有什么问题呢？

Answer 1

您使用的网站似乎不可靠。您是否注意到它为您提供了 3 个XmlRoot 课程？

使用 Visual Studio 中的 Paste XML as classes 功能，我得到了这样的结果：

// NOTE: Generated code may require at least .NET Framework 4.5 or .NET Core/Standard 2.0.
/// <remarks/>
[System.SerializableAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true, Namespace = "http://schemas.datacontract.org/2004/07/Services.Public")]
[System.Xml.Serialization.XmlRootAttribute("Service.ABC", Namespace = "http://schemas.datacontract.org/2004/07/Services.Public", IsNullable = false)]
public partial class ServiceABC
{

    private byte amountField;

    private object customerIDField;

    private byte idField;

    private object updatedDateField;

    /// <remarks/>
    public byte Amount
    {
        get
        {
            return this.amountField;
        }
        set
        {
            this.amountField = value;
        }
    }

    /// <remarks/>
    [System.Xml.Serialization.XmlElementAttribute(IsNullable = true)]
    public object CustomerID
    {
        get
        {
            return this.customerIDField;
        }
        set
        {
            this.customerIDField = value;
        }
    }

    /// <remarks/>
    public byte ID
    {
        get
        {
            return this.idField;
        }
        set
        {
            this.idField = value;
        }
    }

    /// <remarks/>
    [System.Xml.Serialization.XmlElementAttribute(IsNullable = true)]
    public object UpdatedDate
    {
        get
        {
            return this.updatedDateField;
        }
        set
        {
            this.updatedDateField = value;
        }
    }
}

Answer 2

您的根对象 ServiceABC 上缺少命名空间声明。

您似乎还有不正确的嵌套对象：nil="true" 只是表示它是一个可为空的字段。由于缺乏信息，我不得不猜测真正的类型是什么。

[XmlRoot(ElementName="Service.ABC", Namespace = "http://schemas.datacontract.org/2004/07/Services.Public")]
public class ServiceABC
{ 
    [XmlElement(ElementName="Amount")] 
    public int? Amount { get; set; } 

    [XmlElement(ElementName="CustomerID")] 
    public int? CustomerID { get; set; } 

    [XmlElement(ElementName="ID")] 
    public int ID { get; set; } 

    [XmlElement(ElementName="UpdatedDate")] 
    public DateTime? UpdatedDate { get; set; } 
}

dotnetfiddle