ASP.NET中XML转JSON的方法实例

本文实例讲述了ASP.NET中XML转JSON的方法，分享给大家供大家参考。具体如下：

一般在许多应用程序中都将数据存储为XML的格式，而且会将数据以JSON的格式发送到客户端以做进一步处理。要实现这一点，它们必须将XML格式转换为JSON格式。

XML转JSON代码如下：

private static string XmlToJSON(XmlDocument xmlDoc)  

{  

    StringBuilder sbJSON = new StringBuilder();  

    sbJSON.Append("{ ");  

    XmlToJSONnode(sbJSON, xmlDoc.DocumentElement, true);  

    sbJSON.Append("}");  

    return sbJSON.ToString();  

}  

  

//  XmlToJSONnode:  Output an XmlElement, possibly as part of a higher array  

private static void XmlToJSONnode(StringBuilder sbJSON, XmlElement node, bool showNodeName)  

{  

    if (showNodeName)  

        sbJSON.Append("\\"" + SafeJSON(node.Name) + "\\": ");  

    sbJSON.Append("{");  

    // Build a sorted list of key-value pairs  

    //  where   key is case-sensitive nodeName  

    //          value is an ArrayList of string or XmlElement  

    //  so that we know whether the nodeName is an array or not.  

    SortedList childNodeNames = new SortedList();  

  

    //  Add in all node attributes  

    if( node.Attributes!=null)  

        foreach (XmlAttribute attr in node.Attributes)  

            StoreChildNode(childNodeNames,attr.Name,attr.InnerText);  

  

    //  Add in all nodes  

    foreach (XmlNode cnode in node.ChildNodes)  

    {  

        if (cnode is XmlText)  

            StoreChildNode(childNodeNames, "value", cnode.InnerText);  

        else if (cnode is XmlElement)  

            StoreChildNode(childNodeNames, cnode.Name, cnode);  

    }  

  

    // Now output all stored info  

    foreach (string childname in childNodeNames.Keys)  

    {  

        ArrayList alChild = (ArrayList)childNodeNames[childname];  

        if (alChild.Count == 1)  

            OutputNode(childname, alChild[0], sbJSON, true);  

        else  

        {  

            sbJSON.Append(" \\"" + SafeJSON(childname) + "\\": [ ");  

            foreach (object Child in alChild)  

                OutputNode(childname, Child, sbJSON, false);  

            sbJSON.Remove(sbJSON.Length - 2, 2);  

            sbJSON.Append(" ], ");  

        }  

    }  

    sbJSON.Remove(sbJSON.Length - 2, 2);  

    sbJSON.Append(" }");  

}  

  

//  StoreChildNode: Store data associated with each nodeName  

//                  so that we know whether the nodeName is an array or not.  

private static void StoreChildNode(SortedList childNodeNames, string nodeName, object nodeValue)  

{  

    // Pre-process contraction of XmlElement-s  

    if (nodeValue is XmlElement)  

    {  

        // Convert  <aa></aa> into "aa":null  

        //          <aa>xx</aa> into "aa":"xx"  

        XmlNode cnode = (XmlNode)nodeValue;  

        if( cnode.Attributes.Count == 0)  

        {  

            XmlNodeList children = cnode.ChildNodes;  

            if( children.Count==0)  

                nodeValue = null;  

            else if (children.Count == 1 && (children[0] is XmlText))  

                nodeValue = ((XmlText)(children[0])).InnerText;  

        }  

    }  

    // Add nodeValue to ArrayList associated with each nodeName  

    // If nodeName doesn't exist then add it  

    object oValuesAL = childNodeNames[nodeName];  

    ArrayList ValuesAL;  

    if (oValuesAL == null)  

    {  

        ValuesAL = new ArrayList();  

        childNodeNames[nodeName] = ValuesAL;  

    }  

    else  

        ValuesAL = (ArrayList)oValuesAL;  

    ValuesAL.Add(nodeValue);  

}  

  

private static void OutputNode(string childname, object alChild, StringBuilder sbJSON, bool showNodeName)  

{  

    if (alChild == null)  

    {  

        if (showNodeName)  

            sbJSON.Append("\\"" + SafeJSON(childname) + "\\": ");  

        sbJSON.Append("null");  

    }  

    else if (alChild is string)  

    {  

        if (showNodeName)  

            sbJSON.Append("\\"" + SafeJSON(childname) + "\\": ");  

        string sChild = (string)alChild;  

        sChild = sChild.Trim();  

        sbJSON.Append("\\"" + SafeJSON(sChild) + "\\"");  

    }  

    else  

        XmlToJSONnode(sbJSON, (XmlElement)alChild, showNodeName);  

    sbJSON.Append(", ");  

}  

  

// Make a string safe for JSON  

private static string SafeJSON(string sIn)  

{  

    StringBuilder sbOut = new StringBuilder(sIn.Length);  

    foreach (char ch in sIn)  

    {  

        if (Char.IsControl(ch) || ch == '\\'')  

        {  

            int ich = (int)ch;  

            sbOut.Append(@"\\u" + ich.ToString("x4"));  

            continue;  

        }  

        else if (ch == '\\"' || ch == '\\\\' || ch == '/')  

        {  

            sbOut.Append('\\\\');  

        }  

        sbOut.Append(ch);  

    }  

    return sbOut.ToString();  

}

希望本文所述对大家的asp.net程序设计有所帮助。