帮忙看看为什么会出错?怎样改?
出错信息: “未将对象引用设置到对象的实例”app.config中的代码:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
</configSections>
<appSettings>
<add key="connString" value="DataSource=App_Date\tsleyyg.mdb"/>
</appSettings>
</configuration>
方法代码:
public class AccessDB
{
#region 变量声明处
public OleDbConnection Conn;
public OleDbCommand Comm;
public OleDbDataAdapter OleDbAdapter;
public DataSet ds;
public OleDbDataReader dr;
#endregion
#region 数据库连接类生成处
public AccessDB()
{
string connectionString="";
connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;";
connectionString += @System.Configuration.ConfigurationSettings.AppSettings["connString"].ToString();
Conn = new OleDbConnection(connectionString);
Conn.Open();
}
}
出错信息: “未将对象引用设置到对象的实例”app.config中的代码:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
</configSections>
<appSettings>
<add key="connString" value="DataSource=App_Date\tsleyyg.mdb"/>
</appSettings>
</configuration>
方法代码:
public class AccessDB
{
#region 变量声明处
public OleDbConnection Conn;
public OleDbCommand Comm;
public OleDbDataAdapter OleDbAdapter;
public DataSet ds;
public OleDbDataReader dr;
#endregion
#region 数据库连接类生成处
public AccessDB()
{
string connectionString="";
connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;";
connectionString += @System.Configuration.ConfigurationSettings.AppSettings["connString"].ToString();
Conn = new OleDbConnection(connectionString);
Conn.Open();
}
}
解决方案 »
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