每次新項目的時候，都要從頭去找一遍數據庫工具類。這里分享一個簡單實用的C#的通用DbHelper工具類，支持數據連接池。
連接池配置
<connectionStrings>
<add name="dh_web" connectionString="Data Source=xxx.com;Initial Catalog=xx_db;User ID=xx;Password=**;
pooling=true;max pool size=200" providerName="System.Data.SqlClient"/>
</connectionStrings>
DbHelper類
public class DBHelper
{
private static string connectionString = ConfigurationManager.ConnectionStrings["dh_web"].ConnectionString; //不帶參數的執行命令 public static int ExecuteCommand(string safeSql) { using (SqlConnection connection = new SqlConnection(connectionString)) { connection.Open(); SqlCommand cmd = new SqlCommand(safeSql, connection); return cmd.ExecuteNonQuery(); } } //帶參數的執行命令 public static int ExecuteCommand(string sql, params SqlParameter[] values) { using (SqlConnection connection = new SqlConnection(connectionString)) { connection.Open(); SqlCommand cmd = new SqlCommand(sql, connection); cmd.Parameters.AddRange(values); return cmd.ExecuteNonQuery(); } } public static int GetScalar(string safeSql) { using (SqlConnection connection = new SqlConnection(connectionString)) { connection.Open(); SqlCommand cmd = new SqlCommand(safeSql, connection); return Convert.ToInt32(cmd.ExecuteScalar()); } } public static int GetScalar(string sql, params SqlParameter[] values) { using (SqlConnection connection = new SqlConnection(connectionString)) { connection.Open(); SqlCommand cmd = new SqlCommand(sql, connection); cmd.Parameters.AddRange(values); return Convert.ToInt32(cmd.ExecuteScalar()); } } public static SqlDataReader GetReader(string safeSql) { SqlConnection connection = new SqlConnection(connectionString); connection.Open(); SqlCommand cmd = new SqlCommand(safeSql, connection); return cmd.ExecuteReader(CommandBehavior.CloseConnection); } public static SqlDataReader GetReader(string sql, params SqlParameter[] values) { SqlConnection connection = new SqlConnection(connectionString); connection.Open(); SqlCommand cmd = new SqlCommand(sql, connection); cmd.Parameters.AddRange(values); return cmd.ExecuteReader(CommandBehavior.CloseConnection); } public static DataTable GetDataSet(string safeSql) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet ds = new DataSet(); SqlCommand cmd = new SqlCommand(safeSql, connection); SqlDataAdapter da = new SqlDataAdapter(cmd); da.Fill(ds); return ds.Tables[0]; } } public static DataTable GetDataSet(string sql, params SqlParameter[] values) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet ds = new DataSet(); SqlCommand cmd = new SqlCommand(sql, connection); cmd.Parameters.AddRange(values); SqlDataAdapter da = new SqlDataAdapter(cmd); da.Fill(ds); return ds.Tables[0]; } } }
注意：
CommandBehavior.CloseConnection解決了流讀取數據模式下,數據庫連接不能有效關閉的情況.
當某個XXXDataReader對象在生成時使用了CommandBehavior.CloseConnection,那數據庫連接將在XXXDataReader對象關閉時自動關閉.