110,545
社区成员
发帖
与我相关
我的任务
分享求C#的WINFORM数据库操作类,并含使用方法,因为本人刚学C#.
因为本人刚学数C#,现在求一个数据库C#的WINFORM数据库操作类,并含一个使用例子,谢谢.最好能简单讲解一下.
...全文
请发表友善的回复…
发表回复
huangdan_1984 2008-10-07
- 打赏
- 举报
本人也是初学，帮顶
sessisn 2008-10-07
- 打赏
- 举报
经过一晚上研究,终于问题搞定,多谢提供代码的朋友.
格拉 2008-10-06
- 打赏
- 举报
帮顶
sessisn 2008-10-06
- 打赏
- 举报
5#的那个类怎么调用?能做个演示吗?
auex010 2008-10-06
- 打赏
- 举报
5楼的代码写的很清楚了，常见的ADO.NET都有了
sessisn 2008-10-06
- 打赏
- 举报
能现场帮一下我吗??我QQ是:78054.非常感谢!
nihaonbazhou 2008-10-06
- 打赏
- 举报
顶
冷月孤峰 2008-10-06
- 打赏
- 举报
百度一下网上很多的
yunfeng007 2008-10-06
- 打赏
- 举报
public abstract class SqlHelper {
//Database connection strings
public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["SQLConnString1"].ConnectionString;
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
using (SqlConnection conn = new SqlConnection(connectionString)) {
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
}
public static int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(connectionString);
try {
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr;
}
catch {
conn.Close();
throw;
}
}
public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
using (SqlConnection connection = new SqlConnection(connectionString)) {
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
}
public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) {
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters) {
parmCache[cacheKey] = commandParameters;
}
public static SqlParameter[] GetCachedParameters(string cacheKey) {
SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey];
if (cachedParms == null)
return null;
SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length];
for (int i = 0, j = cachedParms.Length; i < j; i++)
clonedParms[i] = (SqlParameter)((ICloneable)cachedParms[i]).Clone();
return clonedParms;
}
private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms) {
if (conn.State != ConnectionState.Open)
conn.Open();
cmd.Connection = conn;
cmd.CommandText = cmdText;
if (trans != null)
cmd.Transaction = trans;
cmd.CommandType = cmdType;
if (cmdParms != null) {
foreach (SqlParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
}
}
sessisn 2008-10-06
- 打赏
- 举报
非常感谢楼上的朋友,通过你这个例子,脑子子里多少有个概念了,还有些不明白就是代码StringBuilder strSql=new StringBuilder();中的StringBuilder();是哪里来的?如果我要显示一条记录代码怎么写?
周公 2008-10-06
- 打赏
- 举报
有一个流传比较广的DbHelper.cs类，里面提供的方法比较全，可以看看，很多人用那个。
周公 2008-10-06
- 打赏
- 举报
/// <summary>
/// 增加一条数据
/// </summary>
public void Add(LTP.Model.Comment model)
{
StringBuilder strSql=new StringBuilder();
strSql.Append("insert into Comment(");
strSql.Append("Title,ArticleID,Content,UserName,UserIP,AddDate,Visible");
strSql.Append(")");
strSql.Append(" values (");
strSql.Append("'"+model.Title+"',");
strSql.Append(""+model.ArticleID+",");
strSql.Append("'"+model.Content+"',");
strSql.Append("'"+model.UserName+"',");
strSql.Append("'"+model.UserIP+"',");
strSql.Append("'"+model.AddDate+"',");
strSql.Append(""+model.Visible+"");
strSql.Append(")");
DbHelperSQL.ExecuteSql(strSql.ToString());
}
/// <summary>
/// 更新一条数据
/// </summary>
public void Update(LTP.Model.Comment model)
{
StringBuilder strSql=new StringBuilder();
strSql.Append("update Comment set ");
strSql.Append("Title='"+model.Title+"',");
strSql.Append("ArticleID="+model.ArticleID+",");
strSql.Append("Content='"+model.Content+"',");
strSql.Append("UserName='"+model.UserName+"',");
strSql.Append("UserIP='"+model.UserIP+"',");
strSql.Append("AddDate='"+model.AddDate+"',");
strSql.Append("Visible="+model.Visible+"");
strSql.Append(" where CommentID="+model.CommentID+"");
DbHelperSQL.ExecuteSql(strSql.ToString());
}
/// <summary>
/// 删除一条数据
/// </summary>
public void Delete(int CommentID)
{
StringBuilder strSql=new StringBuilder();
strSql.Append("delete Comment ");
strSql.Append(" where CommentID="+CommentID);
DbHelperSQL.ExecuteSql(strSql.ToString());
}
周公 2008-10-06
- 打赏
- 举报
using System;
using System.Collections;
using System.Collections.Specialized;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
public abstract class DbHelperSQL
{
//数据库连接字符串(web.config来配置)
//<add key="ConnectionString" value="server=127.0.0.1;database=DATABASE;uid=sa;pwd=" />
protected static string connectionString = ConfigurationSettings.AppSettings["ConnectionString"];
public DbHelperSQL()
{
}
#region 公用方法
public static int GetMaxID(string FieldName,string TableName)
{
string strsql = "select max(" + FieldName + ")+1 from " + TableName;
object obj = GetSingle(strsql);
if (obj == null)
{
return 1;
}
else
{
return int.Parse(obj.ToString());
}
}
public static bool Exists(string strSql, params SqlParameter[] cmdParms)
{
object obj = GetSingle(strSql, cmdParms);
int cmdresult;
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
cmdresult = 0;
}
else
{
cmdresult = int.Parse(obj.ToString());
}
if (cmdresult == 0)
{
return false;
}
else
{
return true;
}
}
#endregion
#region 执行简单SQL语句
/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand(SQLString,connection))
{
try
{
connection.Open();
int rows=cmd.ExecuteNonQuery();
return rows;
}
catch(System.Data.SqlClient.SqlException E)
{
connection.Close();
throw new Exception(E.Message);
}
}
}
}
/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public static object GetSingle(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using(SqlCommand cmd = new SqlCommand(SQLString,connection))
{
try
{
connection.Open();
object obj = cmd.ExecuteScalar();
if((Object.Equals(obj,null))||(Object.Equals(obj,System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch(System.Data.SqlClient.SqlException e)
{
connection.Close();
throw new Exception(e.Message);
}
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public static SqlDataReader ExecuteReader(string strSQL)
{
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(strSQL,connection);
try
{
connection.Open();
SqlDataReader myReader = cmd.ExecuteReader();
return myReader;
}
catch(System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public static DataSet Query(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
DataSet ds = new DataSet();
try
{
connection.Open();
SqlDataAdapter command = new SqlDataAdapter(SQLString,connection);
command.Fill(ds,"ds");
}
catch(System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
return ds;
}
}
#endregion
}
