Use C # to add, delete, modify, and query XML

XML file format

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <messagelist> <br/> <message id = "1"> <br/> <Name> pandatv </Name> <br/> <QQ> 123456 </QQ> <br/> <email> panda@qq.com </Email> <br/> <content> asfdsafasdfasdfsad I am content </content> <br/> <time> </ time> <br/> </message> <br/> </messagelist>

 

Add >>>>

Xmldocument xmld = new xmldocument (); <br/> xmld. load (server. mappath ("app_code/message. XML "); // load the XML file <br/> xmlnode root = xmld. selectsinglenode ("messagelist"); // find the messagelist node </P> <p> int I = xmld. selectsinglenode ("messagelist "). childnodes. count + 1; <br/> xmlelement xml0 = xmld. createelement ("message"); <br/> xml0.setattribute ("ID", I. tostring (); </P> <p> xmlelement xml1 = xmld. createelement ("name"); // create a Name node <br/> xml1.innertext = this.txt name. value. trim (); <br/> xml0.appendchild (xml1); // Add </P> <p> xmlelement xml2 = xmld. createelement ("QQ"); // create a QQ node <br/> xml2.innertext = this.txt QQ. value. trim (); <br/> xml0.appendchild (xml2); // Add </P> <p> xmlelement xml3 = xmld. createelement ("email"); // create an email node <br/> xml3.innertext = this.txt email. value. trim (); <br/> xml0.appendchild (xml3); // Add </P> <p> xmlelement xml4 = xmld. createelement ("content"); // create a content node <br/> xml4.innertext = this.txt content. value; <br/> xml0.appendchild (xml4); // Add </P> <p> xmlelement xml5 = xmld. createelement ("time"); // create a time node <br/> xml5.innertext = datetime. now. tostring ("yyyy-mm-dd"); <br/> xml0.appendchild (xml5); // Add </P> <p> root. appendchild (xml0); </P> <p> xmld. save (server. mappath ("app_code/message. XML "));

 

Delete >>>>

Xmldocument xmld = new xmldocument (); </P> <p> xmld. load (server. mappath ("app_code/message. XML "); </P> <p> xmlnodelist list = xmld. selectsinglenode ("messagelist "). childnodes; </P> <p> foreach (xmlnode VaR in list) <br/>{< br/> xmlelement xmle = (xmlelement) var; </P> <p> If (xmle. getattribute ("ID") = ID) // If the ID is equal to the value of the text, delete <br/>{< br/> xmle. removeall (); <br/> xmld. save (server. mappath ("app_code/message. XML ")) ; // After deletion, remember to save <br/> page. clientscript. registerstartupscript (GetType (), "", "alert ('deleted successfully !! '); ", True); <br/>}< br/> else <br/>{< br/> page. clientscript. registerstartupscript (GetType (), "", "alert ('deletion failed !! '); ", True); <br/>}< br/>}

Change >>>>

Xmldocument xmld = new xmldocument (); <br/> xmld. load (server. mappath ("app_code/message. XML "); </P> <p> xmlnodelist list = xmld. selectsinglenode ("messagelist "). childnodes; </P> <p> foreach (xmlnode xmln in list) <br/>{< br/> xmlelement xmle = (xmlelement) xmln; // format conversion <br/> If (request ["ID"]. equals (xmle. getattribute ("ID") <br/>{< br/> xmle. childnodes [0]. innertext = this.txt name. value; <br/> xmle. chil Dnodes [1]. innertext = this.txt QQ. value; <br/> xmle. childnodes [2]. innertext = this.txt email. value; <br/> xmle. childnodes [3]. innertext = this.txt content. value; </P> <p> xmld. save (server. mappath ("app_code/message. XML "); <br/> page. clientscript. registerstartupscript (this. getType (), "", "alert ('modification successful !!! '); Location. href = 'messagelist. aspx' ", true); <br/>}< br/>}

Query >>>>>

// The following code is implemented by PAGE encoding <br/> xmldocument xmld = new xmldocument (); // construct an XML document <br/> xmld. load (server. mappath ("app_code/message. XML "); // load </P> <p> xmlnodelist list = xmld. selectsinglenode ("messagelist "). childnodes; // obtain the subnode <br/> If (list! = NULL) <br/>{< br/> foreach (xmlnode node in list) <br/>{< br/> xmlelement xmle = (xmlelement) node; // conversion <br/> // you can add it tomorrow.