public abstract class DbHelperSQL
{
public static string connectionString;
static DbHelperSQL()
{
connectionString = ConfigurationSettings.AppSettings["db1"];
}
............一系列数据库访问的静态方法
}现在我想继承这个类,访问另外一个数据库 但为什么老是出错,总是不能分别读取两个连接字符串。
请问这样的写法错在哪里? public class DbHelperSQL1 : DbHelperSQL
{
static DbHelperSQL1() { connectionString = ConfigurationSettings.AppSettings["db2"];
}
}
{
public static string connectionString;
static DbHelperSQL()
{
connectionString = ConfigurationSettings.AppSettings["db1"];
}
............一系列数据库访问的静态方法
}现在我想继承这个类,访问另外一个数据库 但为什么老是出错,总是不能分别读取两个连接字符串。
请问这样的写法错在哪里? public class DbHelperSQL1 : DbHelperSQL
{
static DbHelperSQL1() { connectionString = ConfigurationSettings.AppSettings["db2"];
}
}
public abstract class DbHelperSQL
{
public string connectionString;
public virtual string GetConnectionString()
{
return ConfigurationSettings.AppSettings["db1"];
}
............一系列数据库访问的静态方法
}
public class DbHelperSQL1 : DbHelperSQL
{
public override string GetConnectionString() { return ConfigurationSettings.AppSettings["db2"];
}
}