Input string was not in a correct format error

Question

User1717218719 posted

I have the followig code in which I am recieveing the error "

Input string was not in a correct format." on the line:

 textbx.Text = CDec(tmpTbl("Com").ToString).ToString("0.00")

I am trying to set the value of a textbox on my webpage using the value in the sql datatable

The code I have is the following:

       comComm = New SqlCommand
        With comComm
            .Connection = conConn
            .CommandType = CommandType.Text
            .CommandText = "SELECT * FROM TABLE WHERE (X = @X)"

            .Parameters.AddWithValue("@X", argparam)
         End With

        adpAdap = New SqlDataAdapter(comComm)
        adpAdap.Fill(Dst, "tbl")


        Dim tmpTbl As DataTable = argDst.Tables("tbl")

        If tmpTbl.Rows.Count > 0 Then
            
            txtBx.Text = CDec(tmpTbl("Com").ToString).ToString("0.00")

        End If

Answer 1

User475983607 posted

The error is telling you that tmpTbl("Com") is not formatted a decimal and therefore the command fails.  For example, "1A2" would fail.

Keep in mind, we cannot see the data or the table schema.  I recommend basic troubleshooting to find the value of tmpTbl("Com").  Once you know that basic bit of information you'll probably be able to solve the problem.  Use the Visual Studio debugger to step through your code.

IMHO, it's much easier to format the result using T-SQL than C#.  Given your code I assume the main issue is the decimal in SQL has more than 2 significant figures?

Answer 2

User288213138 posted

Hi E.RU,

textbx.Text = CDec(tmpTbl("Com").ToString).ToString("0.00")

tmpTbl represents System.Data.DataRow,the parameter inside should be a row in the Datatable, not a field in the database.

This demo can be used as a reference.

The code:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load


        Using con As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("constr527").ConnectionString)

            Using cmd As SqlCommand = New SqlCommand("select * from Months", con)
                con.Open()
                Dim da As SqlDataAdapter = New SqlDataAdapter(cmd)
                Dim dt As DataTable = New DataTable()
                da.Fill(dt)
                If dt.Rows.Count > 0 Then
                    TextBox1.Text = CDec(dt(0).Item(0).ToString).ToString("0.00")
                End If
            End Using
        End Using
    End Sub

Best regards,

Sam