'ConfigurationSettings.AppSettings' is obsolete

Warning CS0618 'ConfigurationSettings.AppSettings' is obsolete: 'This method is obsolete, it has been replaced by System.Configuration!System.Configuration.ConfigurationManager.AppSettings' 

app.config文件

<configuration>
　　<appSettings>
　　　　<add key="DBServer" value="user id=sa;password=123456;database=db;server=localhost"/>
　　</appSettings>
</configuration>

代码调用部分

string _connStr = ConfigurationSettings.AppSettings["DBServer"];

使用以下代码替换上述代码

app.config文件

<configuration>

　　<connectionStrings>

　　　　<add name="DBServer" connectionString="user id=sa;password=123456;database=db;server=localhost"/>

　　</connectionStrings>

</configuration>

 

代码调用部分

string _connStr = ConfigurationManager.ConnectionStrings["DBServer"].ToString();

 

上面是针对数据库连接字段connectionString的修改，还有一种是针对appSettings的修改。

对于appSettings仅仅需要修改代码调用函数即可不需要修改app.config文件。

string _ipStr = ConfigurationSettings.AppSettings["IP"];

string _ipStr = ConfigurationManager.AppSettings["IP"].ToString();