Question

ConfigurationManager.ConnectionStrings 未将对象引用设置到对象的实例.

MainWindow.xaml是
using System;using System.Collections.Generic;using System.Configuration;using System.Data.SqlClient;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Navigation;using System.Windows.Shapes;
namespace ADO.Net{ /// <summary> /// MainWindow.xaml 的交互逻辑 /// </summary> public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); }
private void BT_OK_Click(object sender, RoutedEventArgs e) { string connStr = ConfigurationManager.ConnectionStrings["dbConnStr"].ConnectionString; MessageBox.Show(connStr); } }}
配置文件是
<?xml version="1.0" encoding="utf-8" ?><configuration> <connectionStrings> <add name="dbConnStr" connectionString="Data Source=.; Initial Catalog=MyTest;User ID=sa;Password=123456"/> </connectionStrings></configuration>
但是出现这个异常，一直没办法解决 T^T

Answer 1

断点，中断的时候把鼠标移动到ConnectionStrings处，看数组有几个成员，如果为空说明没读到文件，如果有1个以上，试试把索引器从字符串改成下标呢，比如0？