c#—xml读取、增加、修改和删除操作 
1.xml文件格式如下：
<?xml version="1.0" encoding="utf-8"?>
<projects>
<project name="platformframewo" vss-path="platform$/source codhdt$pla~1.sln" />
</projects>
1.读取
dataset ds = new dataset();
ds.readxml(server.mappath(@projects.xml));
datatable dt = ds.tables[0];
return dt;
//得到的datable在前台进行循环输出，省略...
<tr style="font-weight: bold;"> //文字加粗
<td style="border-bottom: solid 2px gray;"> //文字底部加横线
2.新增
xmldocument xmldoc = new xmldocument();
string path = server.mappath(@projects.xml);
xmldoc.load(path);
xmlnode root=xmldoc.selectsinglenode(projects);
xmlelement xe1 = xmldoc.createelement(project);
xe1.setattribute(name, txtprojectname.text);
strvsspath = txtprojectvss.text + $ + txtprojectpath.text + $ + txtprojectsln.text;
xe1.setattribute(vss-path,strvsspath);
root.appendchild(xe1);
xmldoc.save(path);
3.修改
xmldocument xmldoc = new xmldocument();
string path = server.mappath(@projects.xml);
xmldoc.load(path);
xmlnodelist nodelist = xmldoc.selectsinglenode(projects).childnodes;
foreach (xmlnode xn in nodelist)
{
     xmlelement xe = (xmlelement)xn;
     if (xe.getattribute(name) == request[name].tostring())
     {
         xe.setattribute(name, txtprojectname1.text);
         strvsspath = txtprojectvss1.text + $ + txtprojectpath1.text + $ + txtprojectsln1.text;
         xe.setattribute(vss-path, strvsspath);
         xmldoc.save(path);
      }
   }
4.删除
xmldocument xmldoc = new xmldocument();
string path = server.mappath(@projects.xml);
xmldoc.load(path);
xmlnodelist nodelist = xmldoc.selectsinglenode(projects).childnodes;
foreach (xmlnode xn in nodelist)
{
   xmlelement xe = (xmlelement)xn;
   if (xe.getattribute(name) == request[name].tostring())
   {
     xn.parentnode.removechild(xn);
     xmldoc.save(path);
   }
}