Question

C#winform程序连接Access数据库并实现登录功能，我的代码不对，请问正确的怎么写？

try
{
string strConnection = "Provider=Microsoft.Jet.OleDb.4.0;";

strConnection += @"Data SourceC:\Users\pc533\Desktop\1.mdb"; // 定义连接

OleDbConnection objConnection = new OleDbConnection(strConnection);

objConnection.Open();

string sql = "select * from user where username='" + this.textBox1.Text + "' and password='" + this.textBox2.Text + "'";

OleDbCommand cmd = new OleDbCommand(sql, objConnection);
int state = Convert.ToInt32(cmd.ExecuteScalar());//执行sql语句，并返回获得值
if (state == 0 || state > 1)//如果数据中没有记录或有多条记录则抱错
{
this.label3.Text = "用户不存在，请检测用户名和密码是否正确！";
}
else
{
this.label3.Text = "登入成功！";

}
objConnection.Close();

}

catch (Exception es)
{
MessageBox.Show("登录失败！");

}

}

Answer 1

两处错误，第一处改为：
strConnection += @"Data Source=C:\Users\pc533\Desktop\1.mdb"; // 定义连接
第二处改为：
string sql = "select count(*) from user where username='" + this.textBox1.Text + "' and password='" + this.textBox2.Text + "'";

Answer 2

strConnection += @"Data SourceC:\Users\pc533\Desktop\1.mdb"; // 定义连接
不知道是不是掉了个等号。
strConnection += @"Data Source=C:\Users\pc533\Desktop\1.mdb"; // 定义连接

Answer 3

1.
strConnection += @"Data Source=C:\Users\pc533\Desktop\1.mdb"; // 定义连接

2.
user和password是acccess的关键字，如下
string sql = string.Format("select count(*) from [user] where username='{0}' and [password]='{1}'",this.textBox1.Text,this.textBox2.Text);

Answer 4

strConnection += @"Data Source=C:\Users\pc533\Desktop\1.mdb"; // 定义连接

Data Source后面少了个等号