c# - 点击事件查询

Question

我有一个带有文本框的表单，可以从另一个表单的数据 GridView 中查看数据。当表单打开时，它会在文本框中显示从表中选择的数据并修剪文本以使其易于阅读。我可以通过按钮从这个表单的数据库中删除数据，并有一个按钮来关闭表单。我想要一个编辑按钮，这样我就可以更改文本框中的文本并单击保存。到目前为止，当我单击编辑时，关闭按钮文本更改为取消，但仍然关闭了表单，这就是我想要的。我想更改编辑按钮上的文本以进行更新。当点击它更新数据。是否可以为一个按钮设置 2 个 ClickEvents，一个用于开始编辑，另一个用于更新记录？或者显示隐藏按钮并隐藏编辑按钮会更好吗？

public partial class viewForm : Form
{
    DataRowView Data = null;
    public viewForm(DataRowView dr)
    {
        InitializeComponent();
        Data = dr;
        }

    private void closeBTN_Click(object sender, EventArgs e)
    {

        this.Close();
    }

    private void viewForm_Load(object sender, EventArgs e)
    {
        refTxt.Text = Data["Reference"].ToString().Trim();
        firstTxt.Text = Data["First Name"].ToString().Trim();
        surenameTxt.Text = Data["Surename"].ToString().Trim();
        address1Txt.Text = Data["Address Line 1"].ToString().Trim();
        address2Txt.Text = Data["Address Line 2"].ToString().Trim();
        countyTxt.Text = Data["County"].ToString().Trim();
        postTxt.Text = Data["Post Code"].ToString().Trim();
        contactTxt.Text = Data["Contact Number"].ToString().Trim();
        emailTxt.Text = Data["Email Address"].ToString().Trim();
    }

    private void deleteBTN_Click(object sender, EventArgs e)
    {
        if (MessageBox.Show("Customer information will be perminantly deteled. Do you with to continue? ", "Confirm Delete", MessageBoxButtons.YesNo) == DialogResult.Yes)
        {
            string constring = @"Data Source=|DataDirectory|\LWADataBase.sdf";
            string Query = "delete from customersTBL where Reference ='" + this.refTxt.Text + "';";
            SqlCeConnection conDataBase = new SqlCeConnection(constring);
            SqlCeCommand cmdDataBase = new SqlCeCommand(Query, conDataBase);
            SqlCeDataReader myReader;
            try
            {
                conDataBase.Open();
                myReader = cmdDataBase.ExecuteReader();
                MessageBox.Show("Customer information has been deleted", "Deleted Sucessfully");
                while (myReader.Read())
                {

                }
                MessageBox.Show("Please exit the Customers window and re-open to update the table");
                this.Close();
                //displays a system error message if a problem is found
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

    }

    private void editBTN_Click(object sender, EventArgs e)
    {
        firstTxt.ReadOnly = false;
        surenameTxt.ReadOnly = false;
        address1Txt.ReadOnly = false;
        address2Txt.ReadOnly = false;
        countyTxt.ReadOnly = false;
        contactTxt.ReadOnly = false;
        emailTxt.ReadOnly = false;
        postTxt.ReadOnly = false;
        closeBTN.Text = "Cancel";
        deleteBTN.Hide();

    }




}

Answer 1

不可以，同一个按钮不能有两个事件，但是，您可以根据按钮文本执行不同的操作。下面的代码只是为了演示这种可能性，我不确定是否真的理解你的场景，但你可以很容易地从这里改编

private void editBTN_Click(object sender, EventArgs e)
{
    bool notEditable = true;
    if(editBTN.Text == "Update")
    {
        UpdateDataBase();
        editBTN.Text = "Edit";
        deleteBTN.Visible = True;
        notEditable = true;
    }
    else
    {
        deleteBTN.Visible = false;
        editBTN.Text = "Update";
        deleteBTN.Visible = False;
        notEditable = false;
    }
    firstTxt.ReadOnly = notEditable;
    surenameTxt.ReadOnly = notEditable;
    address1Txt.ReadOnly = notEditable;
    address2Txt.ReadOnly = notEditable;
    countyTxt.ReadOnly = notEditable;
    contactTxt.ReadOnly = notEditable;
    emailTxt.ReadOnly = notEditable;
    postTxt.ReadOnly = notEditable;
}