Tools.XmlConfigMerge.ConfigFileManager.SetKeyValue C# (CSharp) Method

		public void SetKeyValue(string key, string value)
        {
			if (key == null || key == string.Empty)
            {
				throw new ApplicationException("Required key is blank or null");
			}
			
            if (value == null)
            {
				throw new ApplicationException("Required value is null");
			}
			
            XmlNode node = GetKeyValueNode(key);
			
            if (node == null)
            {
				XmlNode top = XmlDocument.SelectSingleNode("/configuration");
				
                if (top == null)
                {
					top = XmlDocument.AppendChild(XmlDocument.CreateElement("configuration") );
				}
				
                XmlNode app = top.SelectSingleNode("appSettings");
				
                if (app == null)
                {
					app = top.AppendChild(XmlDocument.CreateElement("appSettings") );
				}
				
                node = app.AppendChild(XmlDocument.CreateElement("add") );
				node.Attributes.Append(XmlDocument.CreateAttribute("key") ).InnerText = key;
				node.Attributes.Append(XmlDocument.CreateAttribute("value") );
			}
			
			node.Attributes["value"].InnerText = value;
		}