XDocument.load（字符串URI）拋出ArgumentNullException

Question

調用

​​3210

，當我得到一個ArgumentNullException以下是異常的詳細信息。它說，「格式」參數是空的 - 但在哪一點我能夠控制這個參數？ 或者我的錯誤究竟是什麼？

> System.ArgumentNullException was unhandled by user code 
>  HResult=-2147467261 
>  Message=Value cannot be null. 
>  Parameter name: format 
>  ParamName=format 
>  Source=mscorlib 
>  StackTrace: 
>  at System.String.FormatHelper(IFormatProvider provider, String format, ParamsArray args) 
>  at System.String.Format(String format, Object[] args) 
>  at System.SR.Format(String resourceFormat, Object[] args) 
>  at System.Xml.XmlException.CreateMessage(String res, String[] args, Int32 lineNumber, Int32 linePosition) 
>  at System.Xml.XmlException..ctor(String res, String[] args, Exception innerException, Int32 lineNumber, Int32 linePosition, String 
> sourceUri) 
>  at System.Xml.XmlTextReaderImpl.Throw(String res, String arg) 
>  at System.Xml.XmlTextReaderImpl.ParseAttributeValueSlow(Int32 curPos, Char quoteChar, NodeData attr) 
>  at System.Xml.XmlTextReaderImpl.ParseAttributes() 
>  at System.Xml.XmlTextReaderImpl.ParseElement() 
>  at System.Xml.XmlTextReaderImpl.ParseElementContent() 
>  at System.Xml.XmlTextReaderImpl.Read() 
>  at System.Xml.Linq.XContainer.ReadContentFrom(XmlReader r) 
>  at System.Xml.Linq.XContainer.ReadContentFrom(XmlReader r, LoadOptions o) 
>  at System.Xml.Linq.XDocument.Load(XmlReader reader, LoadOptions options) 
>  at System.Xml.Linq.XDocument.Load(String uri, LoadOptions options) 
>  at System.Xml.Linq.XDocument.Load(String uri) 

Answer 1

你需要這個

string EnviromentPath = Path.GetDirectoryName(HostingEnvironment.ApplicationPhysicalPath); 

到你的項目目錄 的路徑，然後你應該後

Path.Combine(EnviromentPath,@"AppData\TestAppData.xml"); 

Answer 2

它們組合有一個看看這個：How I use XDocument.Load() to get a file in the application directory

看來文件路徑不正確，試試這個

XDocument xdoc = XDocument.Load(filepath);