private System.ComponentModel.Container components = null;
private System.Data.OleDb.OleDbConnection cn1;
void Connect(OleDbConnection con,string FullPath)
{ string strConn="Provider=Microsoft.Jet.OLEDB.4.0; Data Source= "+ FullPath+ "; extended Properties=Excel 8.0 ;";
con = new OleDbConnection(strConn);
return; }
Connect(cn1,this.openFileDialog1.FileName);
cn1.Open();//出错,提示:未绑定到实例
private System.Data.OleDb.OleDbConnection cn1;
void Connect(OleDbConnection con,string FullPath)
{ string strConn="Provider=Microsoft.Jet.OLEDB.4.0; Data Source= "+ FullPath+ "; extended Properties=Excel 8.0 ;";
con = new OleDbConnection(strConn);
return; }
Connect(cn1,this.openFileDialog1.FileName);
cn1.Open();//出错,提示:未绑定到实例
应该是FullPath设的有问题!
void Connect( ref OleDbConnection con,string FullPath)
Connect(ref cn1,this.openFileDialog1.FileName);
局部变量不能传出来
也可以把
con声明为成员变量
private OleDbConnection con=null;void Connect(OleDbConnection con,string FullPath)
{ string strConn="....";
con = new OleDbConnection(strConn);
return; }
局部变量会被清除的,这件事告诉我要规范的写代码