Question

当进入有两个数据库的第二个表单时，会出现此错误，是我的连接问题还是其他问题？ enter image description here

public partial class MenClothing : Form
{
    OleDbConnection connect1 = new OleDbConnection();

    public MenClothing(string text)
    {
        InitializeComponent();
        txtUsername.Text = text;
    }

    public MenClothing()
    {
        InitializeComponent();


        connect1.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\Student\Downloads\OFFICAL STAC\OFFICAL STAC\StacProductions\DatabaseSaveItem.accdb";


    }

    private int upperCase(string pass)
    {
        int num = 0;
        foreach (char ch in pass)
        {
            if (char.IsUpper(ch))
            {
                num++;
            }
        }
        return num;
    }

    private void btnlogout_Click(object sender, EventArgs e)
    {
        this.Hide();
        Form2 Return = new Form2(txtUsername.Text);
        Return.ShowDialog();
    }

    private void MenClothing_Load(object sender, EventArgs e)
    {

        try
        {
            connect1.Open();

            connect1.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show("Error " + ex);
        }
    }

    private void pictureBox1_Click(object sender, EventArgs e)
    {
        pictureBox1.ImageLocation = ItemUrl.Text;
    }

    private void textBox1_TextChanged(object sender, EventArgs e)
    {
        pictureBox1.ImageLocation = ItemUrl.Text;
    }

    private void button1_Click(object sender, EventArgs e)
    {

        {
            try
            {
                connect1.Open();
                OleDbCommand command = new OleDbCommand();
                command.Connection = connect1;
                command.CommandText = "insert into RegisterItem([Name],[Url],[Description], [Price]) values('" + ItemName.Text + "','" + ItemUrl.Text + "','" + ItemDescription.Text + "','" + ItemPrice.Text + "')";



                command.ExecuteNonQuery();
                MessageBox.Show("Data Saved");
                connect1.Close();
            }
            catch (Exception ex)
            {
                MessageBox.Show("Error " + ex);
                connect1.Close();

            }





                string str = ItemUrl.Text;
                pictureBox1.ImageLocation = str;
                //string str = textBox1.Text;
                // Image img = Image.FromFile(str);
                // pictureBox1.Image = img;

                txtUsername = txtID1;
                ItemName = txtName1;
                ItemDescription = txtDescription1;
                ItemPrice = txtPrice1;

                ItemName.Text = "";
                ItemDescription.Text = "";
                ItemPrice.Text = "";





            }
        }


    private void label5_Click(object sender, EventArgs e)
    {

    }

    private void textBox2_TextChanged(object sender, EventArgs e)
    {

    }

    private void textBox5_TextChanged(object sender, EventArgs e)
    {

    }

    private void btnDelete_Click(object sender, EventArgs e)
    {
        if (txtUsername.Text == txtID1.Text)
        { 

        }
    }
 }
}

Answer 1

在黑暗中只是一个刺，但如果使用文本重载调用构造函数，则不会初始化连接字符串。只有在使用默认构造函数时才会初始化它。

一次处理两个数据库时出错

1 个答案: