Question

用户代码未处理ArgumentException

protected void Button1_Click1(object sender, EventArgs e) { OleDbConnection conn = new OleDbConnection(strConnection); try { conn.Open(); string sql = "select * from Users where user_id='" + this.TextBox1.Text + "' and user_password='" + this.TextBox2.Text + "'"; OleDbCommand cmd = new OleDbCommand(sql, conn); OleDbDataReader dr = cmd.ExecuteReader(); if (this.TextBox1.Text == "" || this.TextBox2.Text == "") { Response.Write("<script>alter('帐号或者密码不能为空')</script>"); } else if (this.TextBox2.Text.Length < 6) { Response.Write("<script>alter('密码不能低于6位')</script>"); } else { if (dr.Read() == true) { //if(dr.GetInt32(2)==0) if ((int)dr["user_power"] == 0) { Response.Redirect("XtEdit.aspx"); } else if ((int)dr["user_power"] == 1) { Response.Redirect("XtEdit.aspx"); } } else { Response.Write("<script>alter('用户名或者密码错误，重新登录')</script>"); } } conn.Close(); } catch (Exception) { Response.Write("<script>alter('数据库链接失败')</script>"); } }

Answer 1

catch (Exception e) { Response.Write("<script>alter('数据库链接失败')</script>"); } catch(Exception e) 的含意是：如果运行中产生错误，则把错误信息保存在变量e中（以便显示给用户或做它用）。