C# 重新使用类连接到第二个数据库
我有sql连接管理器连接到我的数据库,如:C# 重新使用类连接到第二个数据库,c#,asp.net,C#,Asp.net,我有sql连接管理器连接到我的数据库,如: public class SQLConnMgr : Disposable { #region private properties SqlConnection dbconn = new SqlConnection(); private bool _Errors; private string _ErrMsg = string.Empty, _Catalog = string.Empty,
public class SQLConnMgr : Disposable {
#region private properties
SqlConnection dbconn = new SqlConnection();
private bool _Errors;
private string
_ErrMsg = string.Empty,
_Catalog = string.Empty,
_Server = string.Empty,
_UserID = string.Empty,
_Pwd = string.Empty,
_ConnStr = string.Empty;
public SQLConnMgr()
{
this.SetConnection();
this.InitClass();
}
private void SetConnection()
{
AppSettingsReader reader = new AppSettingsReader();
this._Server = (string)reader.GetValue("DBServer", this._Server.GetType());
this._Catalog = (string)reader.GetValue("DBCatalog", this._Catalog.GetType());
this._UserID = (string)reader.GetValue("DBUser", this._UserID.GetType());
this._Pwd = (string)reader.GetValue("DBPwd", this._Pwd.GetType());
}
private void InitClass()
{
if (this._ConnStr == string.Empty)
{
System.Text.StringBuilder cn = new System.Text.StringBuilder();
cn.AppendFormat("Server={0};initial catalog={1};", this._Server, this._Catalog);
cn.AppendFormat("user id={0};password={1};persist security info=True;packet size=4096;Connect Timeout=120", this._UserID, this._Pwd);
dbconn.ConnectionString = cn.ToString();
}
else
{
dbconn.ConnectionString = this._ConnStr;
}
try
{
// open connection to SQL
dbconn.Open();
if (dbconn.State != ConnectionState.Open)
{
this._Errors = true;
this._ErrMsg = "Connection State is not open!";
}
}
catch (System.InvalidOperationException ex)
{
this._ErrMsg = ex.Message;
this._ErrMsg = string.Empty;
//added 1/12/2010 - Johan
SqlConnection.ClearPool(dbconn);
SqlConnection.ClearAllPools();
// attempt the connection again?
dbconn.Close();
InitClass();
}
catch (Exception e)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
sb.Append("Error occured while attempting connect to the database");
sb.Append(e.Message.ToString());
sb.Append(e.Source.ToString());
sb.Append(e.TargetSite.ToString());
this._ErrMsg = sb.ToString();
}
}
所以当我想使用数据库时,我就这样调用这个类:
var db = new SQLConnMgr();
然后,我可以调用此内部的方法,如:
db.GetTableBySQL($"exec usp_Reseller_Get");
我的问题是,如何在另一个类中重新使用此方法来调用另一个数据库,我的意思是,使用:
var db = new SQLConnMgr();
现在使用var bd=newsqlnewdatabaseconnmgr()代码>
为了实现这一点,我创建了另一个类并将SQLConnMgr
像
public class SQLNewDatabaseConnMgr: SQLDataMgr
{
}
但现在我如何调用我的工人阶级的方法来建立新的连接呢?问候
更新
如下面的注释所示,我将SetConnection()
方法设置为受保护的虚拟连接
protected virtual void SetConnection()
{
AppSettingsReader reader = new AppSettingsReader();
this._Server = (string)reader.GetValue("DBServer", this._Server.GetType());
this._Catalog = (string)reader.GetValue("DBCatalog", this._Catalog.GetType());
this._UserID = (string)reader.GetValue("DBUser", this._UserID.GetType());
this._Pwd = (string)reader.GetValue("DBPwd", this._Pwd.GetType());
}
然后在我的新课上我试着
public class SQLNewDatabaseConnMgr: SQLDataMgr
{
private string
_ErrMsg = string.Empty,
_Catalog = string.Empty,
_Server = string.Empty,
_UserID = string.Empty,
_Pwd = string.Empty,
_ConnStr = string.Empty;
public override bool SetConnection()
{
AppSettingsReader reader = new AppSettingsReader();
this._Server = (string)reader.GetValue("DBServer", this._Server.GetType());
this._Catalog = (string)reader.GetValue("DBCatalog", this._Catalog.GetType());
this._UserID = (string)reader.GetValue("DBUser", this._UserID.GetType());
this._Pwd = (string)reader.GetValue("DBPwd", this._Pwd.GetType());
return true;
}
}
但是方法返回我错误:
“SQLConnAllOrdersMgr.SetConnection()”:找不到合适的方法
凌驾
您可以覆盖指示要用于数据库连接的设置的属性。我认为这比让开发人员记住如何检索设置要简单(例如,将
SetConnection
标记为虚拟或抽象时)
您可以将SetConnection()设置为受保护和虚拟,并在SQLNewDatabaseConnMgr上重写它以使用不同的值。您可能还需要重写_Server属性。请参见中的示例。如何重写它?我对c#有点生疏,你能给我一个快速的例子或文档说明我如何实现它吗@HubertJarema实际上,您可能希望将一些代码提升到一个公共抽象基类中,然后有两个子类,一个模仿当前类,另一个模仿新类。这样,类之间的唯一区别是一组特定于每个类的受保护的可重写属性。这只是@HubertJarema建议的一个变体顺便说一句,我对这句话很感兴趣:
This.\u Server=(string)reader.GetValue(“DBServer”,This.\u Server.GetType())代码>。\u服务器
属性是根据自身的值计算出来的?现在在调用中如何将方法调用到控制器中,例如:var db=new SQLConnMgr()代码>我得到:无法创建抽象类或接口'SQLConnMgr'的实例@jonathan对,现在您有了两个新类,因此可以使用var db=new SQLNewDatabaseConnMgr1()代码>。每个派生类都可以描述如何在其覆盖属性中获取连接参数。
public abstract class SQLConnMgr : Disposable
{
SqlConnection dbconn = new SqlConnection();
protected abstract string DBServer { get; }
protected abstract string DBCatalog { get; }
protected abstract string DBUser { get; }
protected abstract string DBPwd { get; }
protected string _Server;
protected string _Catalog;
protected string _UserID;
protected string _Pwd;
public SQLConnMgr()
{
this.SetConnection();
this.InitClass();
}
protected void SetConnection()
{
AppSettingsReader reader = new AppSettingsReader();
this._Server = (string)reader.GetValue(this.DBServer, this._Server.GetType());
this._Catalog = (string)reader.GetValue(this.DBCatalog, this._Catalog.GetType());
this._UserID = (string)reader.GetValue(this.DBUser, this._UserID.GetType());
this._Pwd = (string)reader.GetValue(this.DBPwd, this._Pwd.GetType());
}
}
public class SQLNewDatabaseConnMgr1 : SQLConnMgr
{
protected override string DBServer => "DBServer1";
protected override string DBCatalog => "DBCatalog1";
protected override string DBUser => "DBUser1";
protected override string DBPwd => "DBPwd1";
}
public class SQLNewDatabaseConnMgr2 : SQLConnMgr
{
protected override string DBServer => "DBServer2";
protected override string DBCatalog => "DBCatalog2";
protected override string DBUser => "DBUser2";
protected override string DBPwd => "DBPwd2";
}