类定义开始:
.......
private static string connectionString = "Provider=Microsoft.Jet.OleDb.4.0;Data Source=E:\\Web\\test.mdb";方法1:
OleDbConnection connection = new OleDbConnection(connectionString);
// using (OleDbConnection connection = new OleDbConnection(connectionString))
// {
// do something
// }
方法2:
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
// do something
}如果两个方法都用 using (OleDbConnection connection = new OleDbConnection(connectionString)){}
先调用方法1,再调用方法2,就会出现“ConnectionString 属性尚未初始化。 ”此时,如果方法1注释掉using,而用:
OleDbConnection connection = new OleDbConnection(connectionString);
就不会出错"ConnectionString 属性尚未初始化。 ",为什么?如果两个方法都用using呢?
.......
private static string connectionString = "Provider=Microsoft.Jet.OleDb.4.0;Data Source=E:\\Web\\test.mdb";方法1:
OleDbConnection connection = new OleDbConnection(connectionString);
// using (OleDbConnection connection = new OleDbConnection(connectionString))
// {
// do something
// }
方法2:
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
// do something
}如果两个方法都用 using (OleDbConnection connection = new OleDbConnection(connectionString)){}
先调用方法1,再调用方法2,就会出现“ConnectionString 属性尚未初始化。 ”此时,如果方法1注释掉using,而用:
OleDbConnection connection = new OleDbConnection(connectionString);
就不会出错"ConnectionString 属性尚未初始化。 ",为什么?如果两个方法都用using呢?
private static readonly string connectionString = "Provider=Microsoft.Jet.OleDb.4.0;Data Source=E:\\Web\\test.mdb";