C# 中的 ConfigurationManager類引用方法

?c#添加了Configuration;后，竟然找不到 ConfigurationManager 這個類，后來才發現：雖然引用了using System.Configuration;這個包，但是還是不行的。

后來終于找到一個解決方法，就是在解決方案資源管理器里找到類文件選擇“引用”，然后右擊選擇“添加引用”，并且從 .net 中找到System.Configuration把它加上去就OK啦

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實例：DataGridView顯示數據using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using DevExpress.XtraEditors;
using System.Data.SqlClient;
using System.Configuration;namespace WindowsApplication1
{public partial class XtraForm1 : DevExpress.XtraEditors.XtraForm{public XtraForm1(){InitializeComponent();}private void button1_Click(object sender, EventArgs e){string customers = "select * from Customers";using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["northwind"].ConnectionString)){DataSet dt = new DataSet();SqlDataAdapter da = new SqlDataAdapter(customers, con);da.Fill(dt, "Customers");dataGridView1.AutoGenerateColumns = true;dataGridView1.DataSource = dt;dataGridView1.DataMember = "Customers";}}}
}

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