var 
 reg:TRegIniFile; 
begin 
 reg := TRegIniFile.Create;    //创建实例 
 reg.RootKey := HKey_Local_Machine;  //设置根值 
 if reg.OpenKey('SOFTWARE/MyReg',True) then  //打开 HKey_Local_Machine/SOFTWARE/MyReg,如果MyReg不存在,则自动创建 
 begin 
 //在HKey_Local_Machine/SOFTWARE/MyReg下创建MySec项,然后在MySec中创建一个字符串MyValue,值为China 
 reg.WriteString('MySec','MyValue','China'); 
 end; 
end; 

var 
 reg:TRegIniFile; 
begin 
 reg := TRegIniFile.Create;    //创建实例 
 reg.RootKey := HKey_Local_Machine;  //设置根值 
 if reg.OpenKey('SOFTWARE/MyReg/MySec',True) then 
 begin 
 //删除HKey_Local_Machine/SOFTWARE/MyReg/MySec下MyValue一项 
 reg.DeleteValue('MyValue'); 
 end; 
end; 

var 
 reg:TRegIniFile; 
begin 
 reg := TRegIniFile.Create;    //创建实例 
 reg.RootKey := HKey_Local_Machine;  //设置根值 
 if reg.OpenKey('SOFTWARE/MyReg',True) then 
 begin 
 //删除HKey_Local_Machine/SOFTWARE/MyReg下的MySec 
 reg.EraseSection('MySec'); 
 end; 
end;