xml - Build & keep file into memory and encrypt (C#, WPF, LINQ) -

during creating xml file i'm doing encrypt fields. it's working ok. below code:

create xml class:

private void btnsave_click(object sender, routedeventargs e) {     xmltextwriter xwriter = new xmltextwriter("test.xml", encoding.utf8);     xwriter.formatting = formatting.indented;     xwriter.writestartelement("root");      testviewclassdatacontext dc = new testviewclassdatacontext();     list<test_view> tvq = (from tt in dc.test_views                            select tt).tolist();     var propertiestestview = typeof(test_view).getproperties();     var testviewvalues = new list<string>();      looppropxml(tvq, propertiestestview, testviewvalues, xwriter);      xwriter.writeendelement();     xwriter.close(); }  public void looppropxml<t>(ienumerable<t> queryresult, propertyinfo[] properites, list<string> addedvalues, xmltextwriter xwriter) {     foreach (var qrl in queryresult)     {         var values = new list<object>();         xwriter.writestartelement("tv");         foreach (var property in properites)         {             object value = property.getvalue(qrl, null);             xwriter.writestartelement(property.name.tostring());              desencrypt testencrypt = new desencrypt();             string pass = "qwertyuiop";             string enctext = testencrypt.encryptstring((value == null ? "" : value.tostring()), pass);              xwriter.writestring(enctext);             xwriter.writeendelement();             values.add(value);         }         xwriter.writeendelement();     } } 

here encrypt code took "microsoft academy c#":

static tripledes createdes(string key) {     md5 md5 = new md5cryptoserviceprovider();     tripledes des = new tripledescryptoserviceprovider();     des.key = md5.computehash(encoding.unicode.getbytes(key));     des.iv = new byte[des.blocksize / 8];     return des; }  public string encryptstring(string plaintext, string password) {     byte[] plaintextbytes = encoding.unicode.getbytes(plaintext);     memorystream mystream = new memorystream();     tripledes des = createdes(password);     cryptostream cryptstream = new cryptostream(mystream, des.createencryptor(), cryptostreammode.write);     cryptstream.write(plaintextbytes, 0, plaintextbytes.length);     cryptstream.flushfinalblock();     return convert.tobase64string(mystream.toarray()); } 

how change to:

1 - first build file , keep memory

2 - encrypt it

3 - last save it.

write unencrypted values file:

public void looppropxml<t>(ienumerable<t> queryresult, propertyinfo[] properites, list<string> addedvalues, xmltextwriter xwriter) {     foreach (var qrl in queryresult)     {         var values = new list<object>();         xwriter.writestartelement("tv");         foreach (var property in properites)         {             object value = property.getvalue(qrl, null);             xwriter.writestartelement(property.name.tostring());             xwriter.writestring(value.tostring());             xwriter.writeendelement();             values.add(value);         }         xwriter.writeendelement();     } } 

writing file using xmltextwriter creates , saves if want encrypt file after have done need read contents of file memory again , encrypt it:

private void btnsave_click(object sender, routedeventargs e) {     const string filename = "test.xml";     xmltextwriter xwriter = new xmltextwriter(filename, encoding.utf8);     xwriter.formatting = system.xml.formatting.indented;     xwriter.writestartelement("root");      testviewclassdatacontext dc = new testviewclassdatacontext();     list<test_view> tvq = (from tt in dc.test_views                            select tt).tolist();     var propertiestestview = typeof(test_view).getproperties();     var testviewvalues = new list<string>();      looppropxml(tvq, propertiestestview, testviewvalues, xwriter);      xwriter.writeendelement();     xwriter.close();      string unencrypted = file.readalltext(filename);     desencrypt testencrypt = new desencrypt();     string pass = "qwertyuiop";     string enctext = testencrypt.encryptstring(unencrypted, pass);     file.writealltext(filename, enctext); }