Question

我正在尝试将ASP.NET Web API中的XML响应读入DataSet，以便我可以将其绑定到DropDownList。但是，在阅读回复时，我遇到了Data at the root level is invalid. Line 1, position 1.

Snipp：

WebRequest request = WebRequest.Create("EndPointURL");
request.Method = "GET";
WebResponse response = request.GetResponse();

DataSet ds = new DataSet();

using (StreamReader rdr = new StreamReader(response.GetResponseStream()))
{
    ds.ReadXml(rdr); //EXCEPTION Data at the root level is invalid. Line 1, position 1.
}

XML响应示例：

<ArrayOfPerson xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/MySchema">
    <Person>
        <Address1 xmlns="http://schemas.datacontract.org/2004/07/ClassSchema">123 Main Street</Address1>
        <Address2 xmlns="http://schemas.datacontract.org/2004/07/ClassSchema"">None</Address2>
        ...FOR BREVITY
    </Person>
    <Person>
        ..FOR BREVITY
    </Person>
    .
    .
    .
</ArrayOfPerson>

我已经成功地调用了API的其他端点，所以我有点难过。我在Line 1, position 1看不到任何看似无效的XML字符的内容。什么可能抛出错误？

Answer 1

尝试：

ReadXml(XmlReader)

像这样：

XmlTextReader reader = new XmlTextReader(rdr);
ds.ReadXml(reader);

Answer 2

听起来你可能使用了错误的编码。您可以尝试从HttpWebResponse：

设置编码

        var ds = new DataSet();

        WebRequest request = WebRequest.Create(requestUriString);
        request.Method = "GET";
        using (var response = (System.Net.HttpWebResponse)request.GetResponse())
        {
            // get correct charset and encoding from the server's header
            Encoding encoding;
            try
            {
                encoding = Encoding.GetEncoding(response.CharacterSet);
            }
            catch
            {
                encoding = Encoding.UTF8;
            }

            using (var rdr = new StreamReader(response.GetResponseStream(), encoding))
            {
                ds.ReadXml(rdr);
            }
        }

请注意，这是复杂答案的简化版本：Encoding problem with HttpWebResponse。这些答案建议从返回的HTML中挑选实际编码，并在需要时重新加载流。如果确实需要，可以尝试从XML declaration中选择编码来做类似的事情。

DataSet.ReadXml - 根级别的数据无效

2 个答案: