尝试从DataSet编写Xml的OutOfMemoryException

Question

在C＃中我试图从大数据集中获取xml字符串：

private string GetXmlFromDecomposedPortfolio(string dataSetName, DecomposedPortfolio ptf)
{
     StringWriter writer = new StringWriter();

     System.Data.DataSet ds = new System.Data.DataSet(dataSetName);

     ds.Tables.Add(ptf.Security.Copy());   
     ds.WriteXml((TextWriter)writer, XmlWriteMode.IgnoreSchema);

     return writer.ToString();
}

但我有例外：

System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.     
    at System.String.GetStringForStringBuilder(String value, Int32 startIndex, Int32 length, Int32 capacity)    
    at System.Text.StringBuilder.GetNewString(String currentString, Int32 requiredLength)    
    at System.Text.StringBuilder.Append(Char value)     at System.IO.StringWriter.Write(Char value)  
    at System.Xml.XmlTextWriter.WriteStartElement(String prefix, String localName, String ns)   
    at System.Data.DataTextWriter.WriteStartElement(String prefix, String localName, String ns)  
    at System.Data.XmlDataTreeWriter.XmlDataRowWriter(DataRow row, String encodedTableName)  
    at System.Data.XmlDataTreeWriter.Save(XmlWriter xw, Boolean writeSchema)    
    at System.Data.DataSet.WriteXml(XmlWriter writer, XmlWriteMode mode)   
    at System.Data.DataSet.WriteXml(TextWriter writer, XmlWriteMode mode)    
    at Decompose.Library.Render.GetXmlFromDecomposedPortfolio(String dataSetName, DecomposedPortfolio ptf)   
    at Decompose.Library.Render.SavePE()  
    at Decompose.Library.WorkFlow.ProcessBatch()

有什么建议吗？

Answer 1

首先，您创建了巨大的（显然）xml数据

ds.WriteXml((TextWriter)writer, XmlWriteMode.IgnoreSchema);

将其克隆到string对象writer.ToString();后，所以几乎可以将所需的内存翻倍。

> >结果XML。