c# 为什么用try了访问注册表还会报错
try
{
//读取注册表值
RegistryKey hklm = Registry.LocalMachine;
RegistryKey key = hklm.OpenSubKey("SOFTWARE\\Value\\REG");
string strInstalled = key.GetValue("installed").ToString();
}
catch (NullReferenceException em)
{
MessageBox.Show(em.Message);
}
报错内容 :
System.NullReferenceException:“未将对象引用设置到对象的实例。”