Question

每次我尝试向数据库表添加信息时都会出现错误。

Error: An unhandled exception of type 'System.ArgumentException' occurred in System.Data.dll

Additional information: Input string was not in a correct format.Couldn't store <JHK> in KEY TAG Column.  Expected type is Int32.

到目前为止，这是我的代码。

Imports System
Imports System.Data
Imports System.Data.OleDb

Public Class add_new_key_window

Private Sub TextBox4_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
    Me.Close()
End Sub

Private Sub add_new_key_window_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    'saveRecord()
    management_window.RKM_SystemTableAdapter.Insert(Me.TextBox1.Text, Me.TextBox2.Text, Me.TextBox3.Text, Me.TextBox4.Text, Me.TextBox5.Text, Me.TextBox6.Text, Me.RichTextBox1.Text)
    management_window.RKM_SystemTableAdapter.Fill(management_window.RKM_System_dataDataSet.RKM_System)
    clearTextboxes()
End Sub

'Public Sub saveRecord()
'    Dim cn As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data source=" & Application.StartupPath & "\RKM System data.accdb")
'    Dim str As String

'    Try
'        cn.Open()
'        Dim cmd As New System.Data.OleDb.OleDbCommand("INSERT INTO [RKM System]([KEY TAG], LOCATION, [HOOK NO], [KEY TYPE], BRAND, SERIAL, [TAG COLOR], NOTES) " & _
'                                                      "VALUES ('" & TextBox1.Text & "','" & TextBox2.Text & "','1','" & TextBox3.Text & _
'                                                      "','" & TextBox4.Text & "','" & TextBox5.Text & "','" & TextBox6.Text & _
'                                                      "','" & RichTextBox1.Text & "') ", cn)
'        str = cmd.ExecuteNonQuery
'        MsgBox("The new record was inserted successfully!")

'    Catch ex As Exception
'        MsgBox("Error message: " & ex.Message)
'    End Try  
'    cn.Close()
'End Sub

Public Sub clearTextboxes()
    TextBox1.Clear()
    TextBox2.Clear()
    TextBox3.Clear()
    TextBox4.Clear()
    TextBox5.Clear()
    TextBox6.Clear()
    RichTextBox1.Clear()
End Sub

End Class

Answer 1

您需要将textbox1.text中的值转换为整数 - 目前它要将字符串存储在int32字段中

例如，访问数据库可能具有类型为＆＃34; Number＆＃34;的字段。你需要把它放到哪一类。您试图直接将文本框的内容放入此字段，该字段不是数字，而是字符串。因此你需要＆＃34; Cast＆＃34;使用＆＃34; int.Parse（textbox1.Text）＆＃34;将文本框中的数据转换为正确的类型或类似的。

顺便说一句，在创建像这样的SQL查询时，绝不应该使用内联语句。请使用SQL参数，否则您将面临潜在的SQL注入攻击。

例如（在我的vb中c＃不太好！）：

var cmd = new System.Data.OleDb.OleDbCommand("INSERT INTO table1 (firstname, lastname) VALUES (@firstname, @lastname)");

cmd.Parameters.AddWithValue("@id", (int)textbox1.text);
cmd.Parameters.AddWithValue("@firstname", textbox2.text);

有关详细信息，请参阅

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlparametercollection.addwithvalue(v=vs.110).aspx?cs-save-lang=1&cs-lang=vb#code-snippet-2

Answer 2

Public Sub saveRecord()
    Dim cn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data source=" & 
                 myDbFileName)

    Dim SQL as String = "INSERT INTO [RKM System]([KEY TAG], LOCATION, [HOOK NO], 
             [KEY TYPE], BRAND, SERIAL, [TAG COLOR], NOTES) 
             VALUES (?, ?, ?, ?, ?, ?, ?, ?)"
             ' ? = a place holder for a parameter to be added later

    Try
        cn.Open()

        Using cmd As New OleDBCommand(SQL, cn)
            ' add param values IN ORDER SPECIFIED
            cmd.Parameters.AddWithValue("@p1", Convert.ToInt32(TextBox1.Text))
            cmd.Parameters.AddWithValue("@p2", TextBox2.Text)
            ' etc
            ' number of AddWithValue lines must = number of "?" in SQL

            cmd.ExecuteNonQuery
         End Using            ' disposes of the OLEDbCOmmand object


        MessageBox.Show("The new record was inserted successfully!")

    Catch ex As Exception
        MessageBox.Show("Error message: " & ex.Message)
    End Try
    cn.Close()
End Sub

参数避免SQL注入攻击（阅读此内容）。

由于[KEY TAG]是DB中的整数列，而TextBox1.Text是字符串（总是），您需要使用Convert.ToInt32来转换值（因为它是用户输入，您应该实际使用Integer.TryParse如果他们输入＆＃34; red＆＃34;或＆＃34; ziggy＆＃34;）。

OleDB将命名参数视为简单占位符，因此这会让您遇到麻烦：

 Dim SQL As String = "INSERT INTO Employee (FirstName, LastName) 
            Values (@FName, @LName)"

      cmd.Parameters.AddWithValue("@LName", TextBox1.Text)
      cmd.Parameters.AddWithValue("@FName", TextBox2.Text)

TextBox1将映射到FirstName，因为它是SQL中的第一个列名。

将信息添加到数据库时System.ArgumentException

2 个答案: