我目前收到此错误：＆＃39; System.Data.SqlClient.SqlException＆＃39;在这一行：
int MemberExist = (int)check_Member.ExecuteScalar();
这是我的例外：http://imgur.com/bnp7OcT
我尝试打开与数据库的连接并从文本框中检索数据，并查看ID是否与数据库中的名字和姓氏相匹配。如果是，则继续执行写入PDF文件的代码，如果不是，则将文本框中的某些代码输入数据库。我确定我的代码中还有其他错误，如果有人可以提供帮助，那会很棒但是目前我只是在上面的错误上寻求帮助，这是我到目前为止所做的：
protected void btnSubmit_Click(object sender, EventArgs e)
{
string PostCode = txtPostcode.Text;
string PostCode2 = txtDestinationPostcode.Text;
// Get the connection
SqlConnection DBConnection = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=""E:\DS\Prac5\Part1\App_Data\MyDatabase.mdf"";Integrated Security=True");
SqlDataReader Reader = null;
DBConnection.Open();
SqlCommand check_Member = new SqlCommand("SELECT * FROM Members WHERE MembershipID = FirstName AND LastName = @Txtnput)", DBConnection);
check_Member.Parameters.AddWithValue("@Txtnput", txtMembershipid.Text);
//THIS IS THE LINE BELOW I'm HAVING ISSUES WITH
int MemberExist = (int)check_Member.ExecuteScalar();
if (MemberExist > 0)
{
// if Member exists
PostCodeInfo MatchingPostCode = Find(PostCodeList, PostCode);
if (MatchingPostCode == null)
{
lblOutput.Text = "Your postcode could not be found!";
}
else
{
lblOutput.Text = string.Format("({0},{1})", MatchingPostCode.Locality, MatchingPostCode.State);
}
PostCodeInfo MatchingPostCode2 = Findtwo(PostCodeList, PostCode2);
if (MatchingPostCode2 == null)
{
lblOutput2.Text = "Your postcode could not be found!";
}
else
{
lblOutput2.Text = string.Format("({0},{1})", MatchingPostCode2.Locality, MatchingPostCode2.State);
}
// Put Code here if member text = to member ID
// If not insert member into database
//We keep track of our invoice number by storing it in a plain text file. Using only a variable in memory means that it resets every time our web server turns off!
string NewInvoiceNumber = GenerateNextInvoiceNumber(InvoiceFilePath);
//Creating a document that will be stored on the web server's hard drive
Document MyDoc = new Document();
string PDFPath = Server.MapPath("PDFs");
//Name each of our PDF files uniquely using the invoice number so we don't overwrite them.
FileStream LocalStream = new FileStream(string.Format(@"{0}\Receipt-{1}.pdf", PDFPath, NewInvoiceNumber), FileMode.Create);
PdfWriter.GetInstance(MyDoc, LocalStream);
//Also store the document in memory such that we can send it to the client as an array of bytes
MemoryStream HTTPStream = new MemoryStream();
PdfWriter.GetInstance(MyDoc, HTTPStream);
//Creating the PDF
MyDoc.Open();
//Create the custom fonts we'll use in the PDF
Font Blue = new Font(Font.FontFamily.TIMES_ROMAN, 20f, Font.NORMAL, new BaseColor(System.Drawing.Color.Blue));
Font Grey = new Font(Font.FontFamily.TIMES_ROMAN, 12f, Font.NORMAL, new BaseColor(System.Drawing.Color.Gray));
Font Black = new Font(Font.FontFamily.TIMES_ROMAN, 14f, Font.NORMAL, new BaseColor(System.Drawing.Color.Black));
//We create our Title paragraph seperately because we need to specify the text alignment in order to put it in the center.
Paragraph Title = new Paragraph("Truck delivery receipt\n", Blue);
Title.Alignment = Element.ALIGN_CENTER;
MyDoc.Add(Title);
MyDoc.Add(new Paragraph(string.Format("\nProccessed on " + DateTime.Now.ToString("dd/MM/yyyy h:mm:tt."), Black)));
MyDoc.Add(new Paragraph(string.Format("\nThank you for doing business with Truck Deliveries Co., {0} {1}", txtName.Text, txtLastName.Text)));
MyDoc.Add(new Paragraph(string.Format("Your invoice number is {0}. ", NewInvoiceNumber, Black)));
MyDoc.Add(new Paragraph(string.Format("Please quote this number if you contact support.\n")));
MyDoc.Add(new Paragraph(string.Format("\n")));
Paragraph Heading = new Paragraph("Delivery details\n", Blue);
MyDoc.Add(Heading);
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Add(new Paragraph(string.Format("Your delivery will arrive at {0}, after leaving for delivery at {1} ", txtDeliveryDate.Text, DateTime.Now.ToString("dd/MM/yyyy h:mm:tt."))));
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Add(new Paragraph(string.Format("{0} truck delivery from {1}, {2} {3} to {4}, {5} {6}.", txtNumberoftrucks.Text, txtDeliveryAddress.Text, txtPostcode.Text, lblOutput.Text, txtDestinationDeliveryAddress.Text, txtDestinationPostcode.Text, lblOutput2.Text)));
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Add(new Paragraph(string.Format("Cost of delivery:$19,830.00.")));
MyDoc.Add(new Paragraph(string.Format("Cost of insurance:$289.87.")));
MyDoc.Add(new Paragraph(string.Format("Cost charged (incl. GST):$22102.87. ")));
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Add(new Paragraph(string.Format("Any queries regarding your delivery can be sent to TruckDeliver@Trucks.com, or alternatively you can call 03 9876 5432.")));
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Add(new Paragraph(string.Format("Our business is located at 72 Kaolin Street, VIC, AU. The Fees from this truck delivery will be charged to {0}. We will contact you via the phone number 03 9876 1234 if we experience any issues with yourt order.", txtBillingAddress.Text)));
MyDoc.Add(new Paragraph(string.Format("\n")));
MyDoc.Close();
//Send PDF to client via a HTTP
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", string.Format(@"attachment; filename=Receipt-{0}.pdf", NewInvoiceNumber));
Response.BinaryWrite(HTTPStream.ToArray());
}
else
{
//Member doesn't exist.
string firstname = txtName.Text;
string lastname = txtLastName.Text;
string query = "INSERT INTO Wines(firstname, lastname) " +
"Values('" + firstname + "', '" + lastname + "')";
}
答案 0 :(得分：1)
在@Txtnput之后，您的查询末尾有一个额外的括号。它应该是：
SqlCommand check_Member = new SqlCommand("SELECT * FROM Members WHERE MembershipID = FirstName AND LastName = @Txtnput", DBConnection);