asp.net (C #) application configuration file app.config/web.config Add, delete, change operation _ practical skills

The configuration file, for the program itself, is the foundation and the basis, its essence is an XML file, for configuration file operations, starting from. NET 2.0, is very convenient, providing System [. WEB]. Configuration the namespace of this management function, to use it, you need to add a reference to System.configuration.dll.
For WinForm procedures, use System.Configuration.ConfigurationManager;
For ASP.net procedures, use System.Web.Configuration.WebConfigurationManager;
It's too common to read the contents of a configuration file, but if your program doesn't read the contents of the configuration file, you're embarrassed to take it.
We use the most common AppSettings section as an example:
Assume the following configuration file contents:

Copy Code code as follows:

<?xml version= "1.0" encoding= "Utf-8"?>
<configuration>
<appSettings>
<add key= "y" value= "This is Y"/>
</appSettings>
</configuration>

1. Read the value:
* asp.net:system.web.configuration.webconfigurationmanager.appsettings["y"];
* winform:system.configuration.configurationmanager.appsettings["y"];
2. Add a
asp.net (requires write permission):
Configuration config = webconfigurationmanager.openwebconfiguration (null);
Appsettingssection app = config. AppSettings;
App. Settings.add ("x", "This is X");
Config. Save (configurationsavemode.modified);
WinForm:
Configuration config = configurationmanager.openexeconfiguration (configurationuserlevel.none);
Appsettingssection app = config. AppSettings;
App. Settings.add ("x", "This is X");
Config. Save (configurationsavemode.modified);
3. Modify a
* asp.net
Configuration config = webconfigurationmanager.openwebconfiguration (null);
Appsettingssection app = config. AppSettings;
App. Settings.add ("x", "This is X");
App. settings["X"]. Value = "This are not Y";
Config. Save (configurationsavemode.modified);
* WinForm
Configuration config = configurationmanager.openexeconfiguration (configurationuserlevel.none);
Appsettingssection app = config. AppSettings;
App. Settings.add ("x", "This is X");
App. settings["X"]. Value = "This are not Y";
Config. Save (configurationsavemode.modified);
4. Delete an item
* asp.net
Configuration config = webconfigurationmanager.openwebconfiguration (null);
Appsettingssection app = config. AppSettings;
App. Settings.remove ("X");
Config. Save (configurationsavemode.modified);
* WinForm
Configuration config = configurationmanager.openexeconfiguration (configurationuserlevel.none);
Appsettingssection app = config. AppSettings;
App. Settings.remove ("X");
Config. Save (configurationsavemode.modified);