C # to XML operations: A class that processes XML files (1)

C # Operations XML preliminary (7)

The fourth chapter: General XML Processing method (1) Since we can use a dataset to manipulate an XML file, that's really convenient, and he's perfectly capable of using an XML file as a table. So we can work with one of these C # classes to manipulate XML and do database-like operations: using System; Using System.Text; Using System.IO; Using System.Xml; Using System.Data; namespace XmlBook.Com.Sem.Tools {///<summary>///copyrights: Copyright by Sem IT Department///version: 0.0.1///file: Xmlbook . Com.Sem.Tools.XmlDataBase.cs///Purpose: To provide some ways to treat XML as a database///author: Ouyang Yun @2005-04-09///mailbox: outrace@soueast-motor.com///Modify: </summary> public class XMLdatabase {#region Private membership private string strdatafile = null;///<summary>///number According to the set///</summary> private DataSet myds = null; <summary>///character filter array such as "id= ' 1 ' and username= ' trace '"///</summary> private string strfilter = null; <summary>///sorted fields such as "ID desc,username"///</summary> private string strsort = null; <summary>///the set of field names in the data collection///</summary> private string[] strfields = null; <summary>///data Array in data collection///</summary> private string[] strdata = null; <summary>///template file full path///</summary>private string strtemplatefile = null; #endregion #region Common Properties///<summary>///template file path///</summary> public string Strtemplatefile {Set{this.strte Mplatefile = value;} Get{return This.strtemplatefile}} <summary>///Data File path///</summary> public string Strdatafile {set{this.strdatafile = value;} get{return This.strdatafile;} ///<summary>///character filter array///</summary> public string strfilter {set{this.strfilter = value;}///<sum Mary>///sorted fields///</summary> public string StrSort {set{this.strsort = value;}///<summary>///data collection The field name///</summary> public string[] Strfields {set{this.strfields = value;}}///<summary>///data array in the data collection// /</summary> public string[] Strdata {set{this.strdata = value}}///<summary>///data collection, which can be placed in cache for invocation///</ Summary> public DataSet myds {set{this.myds = value;} Get{return this.myds.}} #endregion public XMLdatabase () {/// TODO: Provide some methods to treat XML as a database//}<summary>///Get the contents of the XML file and fill in the dataset///</summary> private void Open () {try {this.myds = new DataSet (); F Ilestream fin; Fin = new FileStream (This.strdatafile, FileMode.Open, FileAccess.Read, fileshare.readwrite); THIS.MYDS.READXML (Fin); Fin. Close (); catch (Exception ee) {log log = new log (); log. struser = "System"; Log. Strdepartment = "Read XML data"; Log. strFileName = "Com.Sem.Tools.XmlDataBase"; Log. strdescription = ee. message; Log. Writelog (); }///<summary>///writes the results of the operation to XML///</summary> private void Save () {try {this.myDs.WriteXml (this.strdatafil E, Xmlwritemode.writeschema); catch (Exception ee) {log log = new log (); log. struser = "System"; Log. Strdepartment = "Save XML data"; Log. strFileName = "Com.Sem.Tools.XmlDataBase"; Log. strdescription = ee. message; Log. Writelog (); }///<summary>///get specific Data Views///generally in data binding, we can easily generate a view for binding///</summary>///<returns> Data View </re Turns> public DataView Selectview () {if (this.myds = = null) this. Open (); DataView MYDV = new DataView (this.myds.tables[0]); if (strfilter!= null) Mydv.rowfilter = This.strfilter; Mydv.sort = This.strsort; return MYDV; ///<summary>///Get a specific row///use the row because sometimes we just need one or more lines of records///for example, when we judge a login, we just need the line of an ID, and then match its password entry///</ Summary>///<returns> Each row data </returns> public datarow[] Selectrows () {if (this.myds = null) this. Open (); datarow[] myrows = myds.tables[0]. Select (This.strfilter); return myrows; ///<summary>///Inserts a data into the XML///</summary>///<returns> operation succeeded </returns> public bool Insert ( {if (this.myds = null) this. Open (); try {DataRow NewRow = myds.tables[0]. NewRow (); for (int i = 0; i < this.strFields.Length i++) {newrow[this.strfields[i]] = This.strdata[i];} Myds.tables[0]. Rows.Add (NewRow); This. Save (); return true; catch (Exception ee) {log log = new log (); log. struser = "System"; Log. Strdepartment = "Write XML data"; Log. strFileName = "Com.Sem.Tools.XmlDataBase"; Log. strdescription = ee. message; Log. Writelog (); return false; }///<summary>///update data, this time to ensure that Strfields and strdata two array of dimensions consistent///</summary>///<returns> Whether the update succeeded &LT;/R Eturns> public bool Update () {if (this.myds = null) this. Open (); try {datarow[] Editrow = myds.tables[0]. Select (This.strfilter); for (int j=0; j< editrow.length; j) {for (int i = 0; i < this.strFields.Length; i++) {editrow[j][this.strfields[i ] = This.strdata[i]; }} this. Save (); return true; catch (Exception ee) {log log = new log (); log. struser = "System"; Log. strdepartment = "Update xml data"; Log. strFileName = "Com.Sem.Tools.XmlDataBase"; Log. strdescription = ee. message; Log. Writelog (); return false; }///<summary>///delete data///</summary>///<returns> Delete success </returns> public bool Delete () {if ( This.myds = = null) this. Open (); try {datarow[] Editrow = myds.tables[0]. Select (This.strfilter); for (int i=0;i<editrow.length;i++) {editrow[i]. Delete (); } this. Save (); return true; catch (Exception ee) {Log log = new Log (); Log. struser = "System"; Log. strdepartment = "Delete xml data"; Log. strFileName = "Com.Sem.Tools.XmlDataBase"; Log. strdescription = ee. message; Log. Writelog (); return false; }///<summary>///According to a template, create a new XML file (provided that you must have a template file and determine the destination file path)///</summary>///<returns> Write Success < /returns> public bool Create () {try {XmlDocument doc = new XmlDocument (); XmlTextReader reader = new XmlTextReader (This.strtemplatefile); Doc. Load (reader); XmlElement member; XmlNode root = Doc. DocumentElement; for (int i = 0; i < This.strFields.Length, i++) {member = doc. CreateElement (Strfields[i]. ToString ()); Member. innertext = This.strdata[i]. ToString (); Root. AppendChild (member); } XmlTextWriter XmlWriter = new XmlTextWriter (this.strdatafile,null); xmlwriter.formatting = formatting.indented; Doc. Save (XmlWriter); Xmlwriter.close (); Reader. Close (); return true; catch (Exception ee) {log log = new log (); log. struser = "System"; Log. Strdepartment = "New XML data"; Log. strFileName = "Com.Sem.ToolS.xmldatabase "; Log. strdescription = ee. message; Log. Writelog (); return false; }///<summary>///free resources///</summary> public void Clear () {if (this.myds!= null) {this.myDs.Dispose (); } } } }

Class that introduces another log handler, which is sent here Using System; Using System.Xml; Using System.Web; namespace XmlBook.Com.Sem.Tools {///<summary>///copyrights: Copyright by Sem IT Department///version: 0.0.1///file: Xmlbook . Com.Sem.Tools.Log.cs///Purpose: To provide a method of writing Log (that is, to write an error to an XML record)///Author: Owaning @2005-04-09///mailbox: outrace@soueast-motor.com///Modify: </summary> public class Log {#region Private member HttpContext objcontext = httpcontext.current;///<summar y>///log file path///</summary> private string logFile = null; <summary>///operator///</summary> private string struser = null; <summary>///belongs to///</summary> private string strdepartment = null; <summary>///is manipulating the filename///</summary> private string strfilename = null; <summary>///operation time///</summary> private string strtime = null; <summary>///Error description///</summary> private string strdescription = null; #endregion #region Common Properties///<summary>///operator///</summary> public stringstruser {Get{return This.struser} set{this.struser = value;}///<summary>///the filename being manipulated///</summary> pub Lic string strFileName {Get{return this.strfilename; set{this.strfilename = value;}///<summary>///belongs to Lt;/summary> public string Strdepartment {Get{return this.strdepartment} set{this. strdepartment = value;}///< Summary>///operation time///</summary> public string Strtime {Get{return this.strtime;} set{this.strtime = value;}}/ <summary>///Error description///</summary> public string strdescription {Get{return this.strdescription;} set{this. Strdescription = value;} #endregion public log () {///TODO: Provides a way to write log (that is, write the error to the XML record)//}///<summary>///writes the content to the log file///</summar y> public void Writelog () {this.logfile = This.objContext.Server.MapPath ("./log/log.config"); try {xmldocument doc = New XmlDocument (); Doc. Load (This.logfile); XmlElement newlog = doc. CreateElement ("Log"); XmlElement newuser = doc. CreateeLement ("User"); Newuser.innertext = This.struser; Newlog.appendchild (NewUser); XmlElement newdepartment = doc. CreateElement ("Department"); Newdepartment.innertext = this.strdepartment; Newlog.appendchild (newdepartment); XmlElement newfilename = doc. CreateElement ("FileName"); Newfilename.innertext = this. strFileName; Newlog.appendchild (NewFileName); XmlElement newtime = doc. CreateElement ("Time"); Newtime.innertext = DateTime.Now.ToString (); Newlog.appendchild (NewTime); XmlElement newdescription = doc. CreateElement ("Description"); Newdescription.innertext = this.strdescription; Newlog.appendchild (newdescription); Doc. Documentelement.appendchild (Newlog); Doc. Save (This.logfile); The catch (Exception ex) {httpcontext objcontext = httpcontext.current; ObjContext.Response.Write (ex. message); } finally {}}}

so that we can easily take an XML file as a table to manipulate the use of the example, I will give the next article