System.Data.SqlClient的类型初始值设定项引发了异常

Question

This actually worked before but now, not.

string sqlConnString ="Server=server1;Database=Production;Trusted_Connection=true;User ID=User;Password=pwd"; 

        try {
            conn = new SqlConnection(sqlConnString );

And I get the exception. (I know the connection string should be in app.config but that didn't work, either.)

Answer 1

This most likely means that there is an error in your app.config file, eg badly formed XML or unexpected elements. The error happens because the static fields inside SqlConnection read from app.config to determine trace detail level as described here: http://msdn.microsoft.com/en-us/library/ms254503.aspx

(this question is a duplicate of Exception: type initializer for 'system.data.sqlclient.sqlconnection'? )

Answer 2

删除可信和连接之间的下划线。