mysqljoin.aspx.cs

ASP C#代码实例 适合初学人士学习使用

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Configuration;

namespace Example_7_1
{
	/// <summary>
	/// Summary description for MySQLJoin.
	/// </summary>
	public class MySQLJoin : System.Web.UI.Page
	{
		protected System.Web.UI.WebControls.Label SQLLabel;
		protected System.Web.UI.WebControls.Label ResultLabel;
		private readonly string SQLCONNECTIONSTRING = ConfigurationSettings.AppSettings["SQLCONNECTIONSTRING"].ToString();

		private void Page_Load(object sender, System.EventArgs e)
		{
			if(!Page.IsPostBack)
			{
				JoinSQLSelect("Admin");
			}
		}

		private void JoinSQLSelect(String sUserName)
		{
			///从数据库中获取表记录的条数
			String cmdText = "SELECT RealName,Role_Name,Role_Description from Staff "
				+ "INNER JOIN StaffRole ON Staff.Staff_ID = StaffRole.Staff_ID "
				+ "INNER JOIN Role ON Role.Role_ID = StaffRole.Role_ID "
				+ "WHERE Staff_Name = "
				+ "'" + sUserName + "'";
			SqlConnection myConnection = new SqlConnection(SQLCONNECTIONSTRING);
			SqlCommand myCommand = new SqlCommand(cmdText,myConnection);

			///执行数据库查询
			myConnection.Open();
			SqlDataReader dr = myCommand.ExecuteReader();

			String result = "真实名称为： ";
			if(dr.Read())
			{
				result += dr["RealName"].ToString();
				result += "<br>用户角色为： ";
				result += dr["Role_Name"].ToString();
				result += "<br>角色描述为： ";
				result += dr["Role_Description"].ToString();
				result += "<br>";
			}
			else
			{
				result += "<br>用户角色为： ";
				result += "<br>角色描述为： ";
			}
			dr.Close();
			myConnection.Close();	
	
			SQLLabel.Text = cmdText;
			ResultLabel.Text = result;
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{    
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion
	}
}