在vb中将数据插入sqlclient

Question

我需要帮助。我尝试使用以下编码将数据添加到数据库中。但是数据无法保存到数据库中。这意味着点击“保存”按钮

后，数据库中没有任何内容

请检查我的编码。 tq

Imports System.Data.SqlClient

Public Class frmAddNewStaffAdmin

 Dim con As SqlClient.SqlConnection
 Dim dbSource As String
 Dim cmd As SqlClient.SqlCommand

 Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
    Try
        If Len(Trim(cboRole.Text)) = 0 Then
            MessageBox.Show("Please select user type", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            cboRole.Focus()
            Return
        ElseIf Len(Trim(txtStaffID.Text)) = 0 Then
            MessageBox.Show("Please enter Staff ID", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtStaffID.Focus()
            Return
        ElseIf Len(Trim(txtStaffName.Text)) = 0 Then
            MessageBox.Show("Please enter Staff Name", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtStaffName.Focus()
            Return
        ElseIf Len(Trim(txtUsername.Text)) = 0 Then
            MessageBox.Show("Please enter Username", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtUsername.Focus()
            Return
        ElseIf Len(Trim(txtPassword.Text)) = 0 Then
            MessageBox.Show("Please enter Password", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtPassword.Focus()
            Return

        End If

        dbSource = "Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\HMS.mdf;Integrated Security=True;User Instance=True"

        con = New SqlConnection(dbSource)

        con.Open()

        Dim sql As String = "INSERT INTO [User] (Staff_ID, Staff_Role, Staff_Name, Username, Password) VALUES ('" & txtStaffID.Text & "', '" & cboRole.Text & "', '" & txtStaffName.Text & "', '" & txtUsername.Text & "', '" & txtPassword.Text & "' ) "

        cmd = New SqlCommand(sql)

        cmd.Connection = con

        cmd.ExecuteReader()

        MessageBox.Show("Successfully saved", "Record", MessageBoxButtons.OK, MessageBoxIcon.Information)

        con.Close()



    Catch ex As Exception
        MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
    End Try

 End Sub
End Class

Answer 1

使用cmd.ExecuteNonQuery()而不是cmd.ExecuteReader()

Answer 2

您的代码中有两个错误

更改

Dim sql As String = "INSERT INTO [User] (Staff_ID, Staff_Role, Staff_Name, Username, Password) VALUES ('" & txtStaffID.Text & "', '" & cboRole.Text & "', '" & txtStaffName.Text & "', '" & txtUsername.Text & "', '" & txtPassword.Text & "' ) "

到

Dim sql As String = "INSERT INTO [User] (Staff_ID, Staff_Role, Staff_Name, Username, [Password]) VALUES ('" & txtStaffID.Text & "', '" & cboRole.Text & "', '" & txtStaffName.Text & "', '" & txtUsername.Text & "', '" & txtPassword.Text & "' ) "

编辑：

使用像这样的查询

    Dim sql As String = "INSERT INTO [User] (Staff_ID, Staff_Role, Staff_Name, Username, [Password]) VALUES (@StaffID,@Role,@StaffName,@Username,@Password) "

   Cmd.Parameters.AddWithValue("@Staff_ID", txtStaffID.Text)
   Cmd.Parameters.AddWithValue("@Role", cboRole.Text)
   Cmd.Parameters.AddWithValue("@StaffName", txtStaffName.Text)
   Cmd.Parameters.AddWithValue("@Username", txtUsername.Text )
   Cmd.Parameters.AddWithValue("@Password", txtPassword.Text)

1. 将Password更改为[Password]，因为Password是保留关键字。

2. 将cmd.ExecuteReader()更改为cmd.ExecuteNonQuery()

ExecuteNonQuery和ExecuteReader

之间的差异

<强>的ExecuteNonQuery

  

ExecuteNonQuery方法将返回受影响的行数   INSERT，DELETE或UPDATE操作。这个ExecuteNonQuery方法会   仅用于插入，更新和删除，创建和SET   声明。 (Read More about ExecuteNonQuery)

SqlCommand.ExecuteNonQuery MSDN Documentation

<强>的ExecuteReader

  

Execute Reader将用于在执行时返回行集   使用命令对象的SQL查询或存储过程。这个是   仅转发记录的检索，并用于读取表格   从头到尾的值。(Read More about ExecuteReader)

SqlCommand.ExecuteReader MSDN Documentation