wpf窗体按钮取数据库数据，添加配置文件后获取不了连接字符串后窗体启动失败

LemonSmile_ 2013-06-03 09:20:15

求问什么原因，怎么解决
原来没添加配置文件前运行没问题
添加后就启动不成功
断电调试是获取不了连接字符串



using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Data;

using System.Data.SqlClient;

using System.Configuration;



namespace FirstWpfApplication

{

    class SqlHelper

    {

        public static string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;



         

        //public static string connStr = "data source = XXXXXX;database = Test; uid = sa; pwd = xxxxx;";

        //public static DataTable ExecuteDataTable(string sql, params SqlParameter[] parameters) 

        //{

        //    DataTable table = new DataTable();

        //    using (SqlConnection conn = new SqlConnection(connStr)) 

        //    {

        //        conn.Open();

        //        using (SqlCommand cmd = conn.CreateCommand())

        //        {

        //            cmd.CommandText = sql;

        //            cmd.Parameters.AddRange(parameters);



        //            SqlDataAdapter adapter = new SqlDataAdapter(cmd);

        //            adapter.Fill(table);

        //        }

        //        return table;

 

        //    }

        //}



        public static DataTable ExecuteDataTable(string sql,params SqlParameter[] parameters)

        {

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

            DataTable data = new DataTable();

            using (SqlConnection conn = new SqlConnection(connStr))

            {

                using (SqlCommand cmd = conn.CreateCommand())

                {

                    cmd.CommandText = sql;

                    //if (parameters != null)

                    //{

                    //    foreach (SqlParameter parameter in parameters)

                    //    {

                    //        command.Parameters.Add(parameter);

                    //    }

                    //}

                    cmd.Parameters.AddRange(parameters);

                    SqlDataAdapter adapter = new SqlDataAdapter(cmd);

                    adapter.Fill(data);

                }

            }

            return data;

        }



        public static int ExecuteNonQuery(string sql, params SqlParameter[] parameters)

        {

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

            using (SqlConnection conn = new SqlConnection(connStr))

            {

                conn.Open();

                using (SqlCommand cmd = conn.CreateCommand())

                {

                    cmd.CommandText = sql;

                    cmd.Parameters.AddRange(parameters);



                    return cmd.ExecuteNonQuery();

                }

            }

 

        }

    }

}



<?xml version="1.0" encoding="utf-8" ?>

<configuration>

  <connectionStrings>

    <add name ="connStr" connectionString="data source = XXXXXXX;database = Test; uid = sa; pwd = XXXXXX"  providerName="System.Data.SqlClient"/>

  </connectionStrings>

</configuration>

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