Reading Connection string from application Config file
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I Am trying  to  reading my connection string in the Application configuration file.But keep receiving error:The name ConfigurationManager does in exit in current context.After googling the error. i added right on my project add browse to the .Net tab selected the ConfigurationManager  to add it to my project.But still show the same error:    
i call it like this:    
`string sqlConStr = ConfigurationManager.ConnectionStrings["AppConnectionString"].ToString();`    
My application config file:    


    <?xml version="1.0" encoding="utf-8" ?>
    <configuration>
    <connectionStrings>
    <add name="AppConnectionString" connectionString="SERVER=1894; Database=db; UID=loss;  PWD=where;encrypt=no;enlist=false" providerName="System.Data.SqlClient" />
     </connectionStrings>
     </configuration>