请问如何创建和编辑如下xml文档
<?xml   version= "1.0 "   encoding= "GB2312 "   standalone= "yes "   ?>  
-   <Msg   Version= "7 "   MsgID= "2 "   Type= "RadioDown "   DateTime= "2005-11-17   15:30:00 "   SrcCode= "110000X01 "   DstCode= "110000R01 "   Priority= "1 ">
-   <EquipmentInitParamSet>
-   <Equipment   Type= "System ">
-   <Center   SrcCode= "110000X11 ">
-   <!--   测试指令下发平台参数信息  
    -->  
    <Param   Name= "UpURL "   Value= "http://10.1.1.34:8000/receiver "   />  
    <Param   Name= "FTP "   Value= "10.1.1.23 "   />  
    <Param   Name= "FTPPort "   Value= "21 "   />  
    <Param   Name= "FTPUser "   Value= "anonymous "   />  
    <Param   Name= "FTPPassword "   Value= "an@email.com "   />  
    <Param   Name= "FTPPath "   Value= "upload "   />  
    </Center>
-   <Center   SrcCode= "230000X11 ">
    <Param   Name= "UpURL "   Value= "http://10.1.1.34:8000/receiver "   />  
    <Param   Name= "FTP "   Value= "10.1.1.23 "   />  
    <Param   Name= "FTPPort "   Value= "21 "   />  
    <Param   Name= "FTPUser "   Value= "anonymous "   />  
    <Param   Name= "FTPPassword "   Value= "an@email.com "   />  
    <Param   Name= "FTPPath "   Value= "upload "   />  
    </Center>
-   <LogInfo   Type= "Main ">
-   <!--   广播监测设备向测试指令下发平台拨号参数设置，首选
    -->  
    <Param   Name= "Phone "   Value= "01062345678 "   />  
    <Param   Name= "LogName "   Value= "user "   />  
    <Param   Name= "LogPassword "   Value= "password "   />  
    </LogInfo>
-   <LogInfo   Type= "Slave ">
-   <!--   广播监测设备向测试指令下发平台拨号参数设置，备用
    -->  
    <Param   Name= "Phone "   Value= "01062345678 "   />  
    <Param   Name= "LogName "   Value= "user "   />  
    <Param   Name= "LogPassword "   Value= "password "   />  
    </LogInfo>
-   <LogInfo   Type= "Native ">
-   <!--   更改广播监测设备拨号时的传入连接密码设置
    -->  
    <Param   Name= "LogPassword "   Value= "password "   />  
    </LogInfo>
    <Param   Name= "TimeServer "   Value= "10.1.1.22 "   />  
    <Param   Name= "BatteryLevelDownThreshold "   Value= "10.1 "   />