数据类型不匹配条件表达式错误

Question

con.Close();

cmd = new OleDbCommand(@"INSERT INTO tbl_allTransactions VALUES 
     (@transDate, @transType, @transDesc, @transAmount, @transCategory, 
      @transFreq, @transPayVia, @transPaid, @transToPay, @transNextPay, 
      @transStatus, @transMonth, @transWeek, @transYear, @c_name ,@transMode)", con);

cmd.Parameters.AddWithValue("@transDate", firstPay.ToShortDateString());
cmd.Parameters.AddWithValue("@transType", cbtransType.Text);
cmd.Parameters.AddWithValue("@transDesc", txtDesc.Text);
cmd.Parameters.AddWithValue("@transAmount", txtMoney.Text);
cmd.Parameters.AddWithValue("@transCategory", cbCategory.Text);
cmd.Parameters.AddWithValue("@transFreq", cbFreq.Text);
cmd.Parameters.AddWithValue("@transPayVia", cbPay.Text);
cmd.Parameters.AddWithValue("@transPaid", i);
cmd.Parameters.AddWithValue("@transToPay", txtpayments.Text);

if (i <= (totPayments - 1))
{
    cmd.Parameters.AddWithValue("@transNextPay", nextPay.ToShortDateString());
}

if (i == totPayments)
{
    cmd.Parameters.AddWithValue("@transNextPay", firstPay.ToShortDateString());
}            

if (i <= (totPayments - 1))
{
    transStatus = "Uncleared";
    cmd.Parameters.AddWithValue("@transStatus", transStatus);
}

if (i == totPayments)
{
    transStatus = "Cleared";
    cmd.Parameters.AddWithValue("@transStatus", transStatus);
}   

cmd.Parameters.AddWithValue("@transMonth", whichMonth);
cmd.Parameters.AddWithValue("@transWeek", whichWeek);
cmd.Parameters.AddWithValue("@transYear", whichYear);
cmd.Parameters.AddWithValue("@c_name", cName);
transMode = cbDuration.Text;
cmd.Parameters.AddWithValue("@transMode", transMode);
con.Open();
int j = Convert.ToInt32(cmd.ExecuteNonQuery());

if (j == 1)
{
    j = 0;
    //  nextPay = firstPay = DateTime.Now;
}
con.Close();

Answer 1

Using AddWithValue means that the datatype for the parameter value is determined by the value itself. So, for example, the datatype of the parameter @transDate is a string, not a date because you use the ToShortDateString() conversion. Of course this requires that the field updated by the parameter is a string not a date.

You need to check, if every parameter goes to update a compatible field type, Another example could be the parameter @transAmount . Is the database field a string? You pass the Text property of a textbox, so it should be a string.

There is another potential problem. You should be sure that the parameters @transNextDay and @transStatus are always added to the collection. The current code present the possibility that these parameters are not added (i > totPayments)