Error Converting datatype nvarchar to int from c# to sql

Question

Hi Guys please help me out in my code where I got stuck and went wrong, I have two tables; one employee table and another branch table. The branch id will be stored in employee table which is a foreign key. When I'm inserting the data through stored procedure where I kept the code like bleow

Create procedure [dbo].[Insertemployee]

@d28 int,@d1 nchar(15),@d2 nchar(30),@d3 int,@d4 nchar(10),@d5 nchar(20),@d6 nchar(30),@d7 varchar(100),@d8 nchar(100),@d9 nchar(10),@d10 nchar(10),@d11 nchar(30),@d12 nchar(30),@d13 nchar(30),@d14 nchar(30),@d15 nchar(30),@d16 date,@d17 varchar(100),@d18 int,@d19 int,@d20 int,@d21 int,@d22 int,@d23 int,@d24 int,@d25 image,@d26 date,@d27 date,@d29 nchar(10)
AS
    BEGIN
        SET NOCOUNT ON
    BEGIN TRY
        BEGIN TRANSACTION
insert into Employee(Id,StaffID,StaffName,Branchid,Gender,DOB,FatherName,PermanentAddress,Country,PhoneNo,MobileNo,DateOfJoining,VisaNumber,PassportNumber,PassportExpiryDate,NationalityID,NationalityIDExpiryDate,Designation,BasicSalary,CostOfAllowance,HRA,TeaAndSnacks,Bonus,Loan,OtherDeduction,Picture,createddate,lastmodified,Active) VALUES (@d28,@d1,@d2,(select branchid from Branch where Branch.BranchName=@d3),@d4,@d5,@d6,@d7,@d8,@d9,@d10,@d11,@d12,@d13,@d14,@d15,@d16,@d17,@d18,@d19,@d20,@d21,@d22,@d23,@d24,@d25,@d26,@d27,@d29);
COMMIT TRANSACTION
    END TRY
        BEGIN CATCH
            IF @@TRANCOUNT >0
            BEGIN
                ROLLBACK TRANSACTION
            END
            EXECUTE uspLogError 
        END CATCH
END;`

and my front end code is below

 cmd = new SqlCommand("InsertEmployee");
            cmd.CommandType = CommandType.StoredProcedure;
                cmd.Connection = con;
            cmd.Parameters.AddWithValue("@d28",txtID.Text);

                cmd.Parameters.AddWithValue("@d26", System.DateTime.Now);
                cmd.Parameters.AddWithValue("@d27", System.DateTime.Now);

            cmd.Parameters.AddWithValue("@d1", txtStaffID.Text);

                cmd.Parameters.AddWithValue("@d2",txtStaffName.Text);
                cmd.Parameters.AddWithValue("@d3",txtDepartment.Text);
                cmd.Parameters.AddWithValue("@d4",cmbGender.Text);
                cmd.Parameters.AddWithValue("@d6",txtFatherName.Text);
                cmd.Parameters.AddWithValue("@d7",txtPAddress.Text);
                cmd.Parameters.AddWithValue("@d8",txtTAddress.Text);
                cmd.Parameters.AddWithValue("@d9",txtPhoneNo.Text);
                cmd.Parameters.AddWithValue("@d10",txtMobileNo.Text);
                cmd.Parameters.AddWithValue("@d11",dtpDateOfJoining.Value);
                cmd.Parameters.AddWithValue("@d12",visanumber.Text.Trim());
                cmd.Parameters.AddWithValue("@d14",PassportExpirydate.Text);
                cmd.Parameters.AddWithValue("@d15",NationalityID.Text.Trim());
            if (NationalityID.Text == "")
            {
                cmd.Parameters.AddWithValue("@d16", "");
            }
            else
            {
                cmd.Parameters.AddWithValue("@d16", NationalityExpirydate.Value);
            }
                cmd.Parameters.AddWithValue("@d17",txtDesignation.Text.Trim());
                cmd.Parameters.AddWithValue("@d13",Passportnumber.Text.Trim());
                cmd.Parameters.AddWithValue("@d18",Convert.ToInt32(txtBasicSalary.Text.Trim()));
                if (txtLIC.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d19", 0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d19",Convert.ToInt32(txtLIC.Text.Trim()));

                }
                if (txtGrpInsurance.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d21", 0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d21",Convert.ToInt32(txtGrpInsurance.Text.Trim()));
                }
                if (txtFamilyBenefitFund.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d22",0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d22",Convert.ToInt32(txtFamilyBenefitFund.Text.Trim()));
                }
                if (txtLoans.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d23",0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d23",Convert.ToInt32(txtLoans.Text.Trim()));
                }
                if (txtOtherDeductions.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d24",0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d24",Convert.ToInt32(txtOtherDeductions.Text.Trim()));
                }
                if (txtIncomeTax.Text == "")
                {
                    cmd.Parameters.AddWithValue("@d20",0);
                }
                else
                {
                    cmd.Parameters.AddWithValue("@d20",Convert.ToInt32(txtIncomeTax.Text.Trim()));
                }
            cmd.Parameters.AddWithValue("@d29", chkActive.Text);
                cmd.Parameters.AddWithValue("@d5",DOB.Text);
                MemoryStream ms = new MemoryStream();
                Bitmap bmpImage = new Bitmap(pictureBox1.Image);

                bmpImage.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

                byte[] data = ms.GetBuffer();
                SqlParameter p = new SqlParameter("@d25", SqlDbType.Image);
                p.Value = data;
                cmd.Parameters.Add(p);
                cmd.ExecuteNonQuery();

Answer 1

I think the above answer is correct and he find the issues as well(Congrats). But the actual problem here is the Parameters.AddWithValue. It will not allows you to specify the type and will cause this kind of datatype conversion errors. So What i suggest you is, use Parameters.Add() instead for Parameters.AddWithValue() So that you can specify the type of expecting data and there by able to validate the input. you can see the below example(which help you to solve the issue as well):

cmd.Parameters.Add("@d28", SqlDbType.Int).Value = int.Parse(txtID.Text.Trim());

Where SqlDbType is an Enumeration which Specifies SQL Server-specific data type of a field, property, for use in a SqlParameter. int.TryParse() will be another best suggestion for you to perform error free conversion from string to integer.

Update : It seems The SP accepts values of different types, but you are giving all as string(.Text). This will create the same issue, So changing only "@d28" will not solve the issue, Try to read the attached link and make necessary changes in the code.

Answer 2

You are passing few fields as string to DB datatype int :

cmd.Parameters.AddWithValue("@d28",txtID.Text);

cmd.Parameters.AddWithValue("@d3",txtDepartment.Text);

you should convert them to int prior passing it to db

 cmd.Parameters.AddWithValue("@d28",Convert.ToInt32(txtID.Text.Trim()));
  cmd.Parameters.AddWithValue("@d3",Convert.ToInt32(txtDepartment.Text.Trim()));

Just curious how come your txtDepartment be type of int , either you have to make a check whether there is string being passed or its an number . If it accepts only number you might have to check the value being passed to txtDepartment.Text and vice -versa.

Answer 3

d3 field can accept int but you are passing string`

default type of TextBox is string

you can fix this by converting to int

cmd.Parameters.AddWithValue("@d3",txtDepartment.Text);

to

 cmd.Parameters.AddWithValue("@d3",Convert.ToInt(txtDepartment.Text));