基于数据库的资源管理器简单版

来源：互联网发布：英语翻译网站知乎编辑：程序博客网时间：2024/05/01 15:33

说明：

用ADO.NET技术，将数据库连接起来，用winform的形式，将其功能展现出来。

自学代码，有不足指出请多多指教。。。。

有想法也可评论

一起学习，一起探讨ha

下面代码：

winform控件的代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Configuration;
namespace 资料管理器
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
/// <summary>
/// 加载主级目录，并调用递归方法
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Form1_Load(object sender, EventArgs e)
{
List<Category> list = GetCatagoryBytfrientId(-1);//在数据库里将主级目录读出
LoadGategory(list, tv.Nodes);
}
/// <summary>
/// 递归方法，将集合加载到控件上
/// </summary>
/// <param name="list"></param>
/// <param name="nodes"></param>
private void LoadGategory(List<Category> list, TreeNodeCollection nodes)
{
foreach (Category item in list)
{
TreeNode tn= nodes.Add(item.TName);
tn.Tag = item.TId;
//根据数据库表的内容分析出要这样调用方法
//递归方法
LoadGategory( GetCatagoryBytfrientId(item.TId),tn.Nodes);

}
}
/// <summary>
/// 将数据库的数据加载到集合里面
/// </summary>
/// <param name="v"></param>
/// <returns></returns>
private List<Category> GetCatagoryBytfrientId(int v)
{
List<Category> list = new List<Category>();
string sql = "SELECT tID,TName FROM category WHERE tparentid=" + v;
SqlDataReader reader= SQLHelper.ExcuteReader(sql);
if (reader.HasRows)
{
while (reader.Read())
{
Category category = new Category();
category.TId = Convert.ToInt32(reader["tid"]);
category.TName = reader["tName"].ToString();
list.Add(category);
}
}
return list;
}
/// <summary>
/// 双击事件，点击后显示三级内容
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void tv_MouseDoubleClick(object sender, MouseEventArgs e)
{
//错误判别方法
//if (tv.SelectedNode.NextNode!=null)
//{
// listBox1.DataSource = GetContntInfo(Convert.ToInt32(tv.SelectedNode.Tag));
// listBox1.DisplayMember = "DNAme";

//}
listBox1.DataSource = GetContntInfo(Convert.ToInt32(tv.SelectedNode.Tag));
listBox1.DisplayMember = "DNAme";
}
/// <summary>
/// 将数据库的苏剧加载到集合里面
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
private List<ContentInfo> GetContntInfo(int id)
{
List<ContentInfo> list = new List<ContentInfo>();
string sql = "SELECT did,dname FROM contentinfo WHERE dtid=" + id;
SqlDataReader reader= SQLHelper.ExcuteReader(sql);
if (reader.HasRows)
{
while (reader.Read())
{
ContentInfo coninfo = new ContentInfo();
coninfo.DId = Convert.ToInt32(reader["did"]);
coninfo.DName = reader["dNAme"].ToString();
list.Add(coninfo);
}
}
return list;
}
/// <summary>
/// 选择事件，将选定的内容显示到文本框控件中
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
//将选定的内容转换为所需类型
ContentInfo con= listBox1.SelectedItem as ContentInfo;
textBox1.Text = GetContentInfoText(con.DId);
}
/// <summary>
/// 返回首首行首列，即将内容返回
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
private string GetContentInfoText(int id)
{
string sql = "SELECT dcontent FROM Contentinfo WHERE did=" + id;
return SQLHelper.ExcuteScalar(sql).ToString();
}
}
}

SQLHelp类：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Configuration;
namespace 资料管理器
{
public class SQLHelper
{
static readonly string str = ConfigurationManager.ConnectionStrings["strSQL"].ConnectionString;
public static int ExcuteNonQuary(string sql,params SqlParameter[]param)
{
using (SqlConnection con=new SqlConnection(str))
{
using (SqlCommand com=new SqlCommand(sql,con))
{
con.Open();
com.Parameters.AddRange(param);
return com.ExecuteNonQuery();
}
}
}
public static object ExcuteScalar(string sql, params SqlParameter[] param)
{
using (SqlConnection con = new SqlConnection(str))
{
using (SqlCommand com = new SqlCommand(sql, con))
{
con.Open();
com.Parameters.AddRange(param);
return com.ExecuteScalar();
}
}
}
public static SqlDataReader ExcuteReader(string sql, params SqlParameter[] param)
{
SqlConnection con = new SqlConnection(str);
using (SqlCommand com=new SqlCommand(sql,con))
{
try
{
con.Open();
return com.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
con.Close();
con.Dispose();
throw ex;
}
}
}
}
}

还有其余几个简单类，可自行写出，这里就不做赘述了。。。

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