如何使用C＃检查注册表值是否存在？

Question

如何通过C＃代码检查注册表值是否存在？ 这是我的代码，我想检查'开始'是否存在。

public static bool checkMachineType() 
{ 
    RegistryKey winLogonKey = Registry.LocalMachine.OpenSubKey(@"System\CurrentControlSet\services\pcmcia", true); 
    string currentKey= winLogonKey.GetValue("Start").ToString(); 

    if (currentKey == "0") 
     return (false); 
    return (true); 
} 

Answer 1

对于注册表键，您可以检查它是否为空后得到它。这将是，如果它不存在。

对于注册表值，您可以获取当前键的值的名称，并检查该数组是否包含所需的值名称。

Answer 2

string keyName=@"HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\pcmcia"; 
string valueName="Start"; 
if (Registry.GetValue(keyName, valueName, null) == null) 
{ 
    //code if key Not Exist 
} 
else 
{ 
    //code if key Exist 
} 

Answer 3

public static bool registryValueExists(string hive_HKLM_or_HKCU, string registryRoot, string valueName) 
{ 
    RegistryKey root; 
    switch (hive_HKLM_or_HKCU.ToUpper()) 
    { 
     case "HKLM": 
      root = Registry.LocalMachine.OpenSubKey(registryRoot, false); 
      break; 
     case "HKCU": 
      root = Registry.CurrentUser.OpenSubKey(registryRoot, false); 
      break; 
     default: 
      throw new System.InvalidOperationException("parameter registryRoot must be either \"HKLM\" or \"HKCU\""); 
    } 

    return root.GetValue(valueName) != null; 
} 

Answer 4

RegistryKey rkSubKey = Registry.CurrentUser.OpenSubKey(" Your Registry Key Location", false); 
     if (rkSubKey == null) 
     { 
      // It doesn't exist 
     } 
     else 
     { 
      // It exists and do something if you want to 
     } 

Answer 5

 internal static Func<string, string, bool> regKey = delegate (string KeyLocation, string Value) 
     { 
      // get registry key with Microsoft.Win32.Registrys 
      RegistryKey rk = (RegistryKey)Registry.GetValue(KeyLocation, Value, null); // KeyLocation and Value variables from method, null object because no default value is present. Must be casted to RegistryKey because method returns object. 
      if ((rk) == null) // if the RegistryKey is null which means it does not exist 
      { 
       // the key does not exist 
       return false; // return false because it does not exist 
      } 
      // the registry key does exist 
      return true; // return true because it does exist 
     }; 

用法：

 // usage: 
     /* Create Key - while (loading) 
     { 
      RegistryKey k; 
      k = Registry.CurrentUser.CreateSubKey("stuff"); 
      k.SetValue("value", "value"); 
      Thread.Sleep(int.MaxValue); 
     }; // no need to k.close because exiting control */ 


     if (regKey(@"HKEY_CURRENT_USER\stuff ... ", "value")) 
     { 
      // key exists 
      return; 
     } 
     // key does not exist 

Answer 6

 RegistryKey test9999 = Registry.CurrentUser; 

     foreach (var item in test9999.GetSubKeyNames()) 
     { 
      if (item.ToString() == "SOFTWARE") 
      { 
       test9999.OpenSubKey(item); 

       foreach (var val in test9999.OpenSubKey(item).GetSubKeyNames()) 
       { 
        if(val.ToString() == "Adobe") { 
         Console.WriteLine(val+ " found it "); 
        } 
       } 
      } 
     }