Question

以下是代码：

Private m_cn As New SqlConnection
Private m_DA As SqlDataAdapter
Private m_CB As SqlCommandBuilder
Private m_DataTable As New DataTable
Private m_intRowPosition As Integer = 0


Private Sub InsertDatabaseItem_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    m_cn.ConnectionString = "Data Source=TREVOR-PC\SQLSERVEREXPRESS;Initial Catalog=Milk Convience Products;Integrated Security=True"

    m_cn.Open()
    m_DA = New SqlDataAdapter("Select * From ProductIndex", m_cn)
    m_CB = New SqlCommandBuilder(m_DA)

    txtBarcode.Focus()

End Sub

Private Sub btnOK_Click(sender As Object, e As EventArgs) Handles btnOK.Click
    Dim cmd As New SqlCommand(("INSERT INTO ProductIndex VALUES(" &
                                "@ID," &
                                "@Name," &
                                "@Price," &
                                "@Desc)" &
                                "@Barcode)"), m_cn)

    cmd.Parameters.Add("@ID", SqlDbType.Int)
    cmd.Parameters("@ID").Value = txtID.Text
    cmd.Parameters.Add("@Name", SqlDbType.VarChar)
    cmd.Parameters("@Name").Value = txtName.Text
    cmd.Parameters.Add("@Price", SqlDbType.Money)
    cmd.Parameters("@Price").Value = txtPrice.Text
    cmd.Parameters.Add("@Desc", SqlDbType.VarChar)
    cmd.Parameters("@Desc").Value = txtDesc.Text
    cmd.Parameters.Add("@Barcode", SqlDbType.BigInt)
    cmd.Parameters("@Barcode").Value = txtBarcode.Text

    cmd.ExecuteNonQuery()

    MsgBox("Success!", MsgBoxStyle.Information, "SUCCESS")

    Me.Hide()

    txtID.Clear()
    txtName.Clear()
    txtPrice.Clear()
    txtDesc.Clear()
    txtBarcode.Clear()

    m_cn.Close()
    m_cn.Dispose()
End Sub


Private Sub btnCancel_Click(sender As Object, e As EventArgs) Handles btnCancel.Click
    Me.Hide()
End Sub

单击btnOK以输入新数据库项后，会发生异常并显示：无法将参数值从String转换为Int32。

我做了一些调试，发现错误发生在“cmd.Parameters（”@ Barcode“）之后.Value = txtBarcode.Text”代码行

Answer 1

cmd.Parameters.Add("@Barcode", SqlDbType.BigInt)
cmd.Parameters("@Barcode").Value = txtBarcode.Text

您正在尝试将txtBarcode.Text强制转换为大整数。这应该通过显式转换值来完成。您的测试用例可能是空字符串或其他无法转换的字符串值。

注意重新阅读您的代码这也可能是Id和Price参数的问题。

尝试将值添加到SQL数据库时，无法将参数值从String转换为Int32

1 个答案: