C# WinForm中第二个窗体仅显示半秒的解决咨询

我运行程序时，添加供应商的窗体仅打开半秒就关闭了。我是编程新手，刚接触C#，目标是实现一个带添加按钮的ListView，用于添加商品（Goods）和供应商（Suppliers）。

相关代码 #

MainForm.cs #

namespace Supply_business.Forms
{
    public partial class MainForm : Form
    {
        public Contracts Contract;
        public MainForm()
        {
            Contract = new Contracts();
            InitializeComponent();
        }

        private void DisplayContent()
        {
            lsview2.Items.Clear();
            Contract.Goods.Sort();
            lsview1.Items.Clear();
            Contract.Suppliers.Sort();
            foreach (var supplier in Contract.Suppliers)
            {
                ListViewItem lvi = new ListViewItem(supplier.Name);
                lvi.SubItems.Add(supplier.Email);
                lvi.Tag = supplier;
                lsview1.Items.Add(lvi);
            }
            foreach (var good in Contract.Goods)
            {
                ListViewItem lvi = new ListViewItem(good.Name);
                lvi.SubItems.Add(good.Description);
                lvi.SubItems.Add(good.Price.ToString());
                lvi.SubItems.Add(good.Quantity.ToString());
                lvi.Tag = good;
                lsview2.Items.Add(lvi);
            }
        }

        private void AddBtn_Click(object sender, EventArgs e)
        {
            AddEditContract addEditContract = new AddEditContract();
            Good good = new Good();
            addEditContract.thisGood = good;

            if (addEditContract.ShowDialog() == DialogResult.OK)
            {
                Contract.Goods.Add(good);
                DisplayContent();
            }
        }

        private void AddBtn2_Click(object sender, EventArgs e)
        {
            AddEditSuppliercs addEditSuppliercs = new AddEditSuppliercs();
            Supplier supplier = new Supplier();
            addEditSuppliercs.thisSupplier = supplier;

            if (addEditSuppliercs.ShowDialog() == DialogResult.OK)
            {
                Contract.Suppliers.Add(supplier);
                DisplayContent();
            }
        }
    }
}

AddEditSuppliercs.cs #

public partial class AddEditSuppliercs : Form
{
    public Supplier thisSupplier { get; set; }
    public AddEditSuppliercs()
    {
        InitializeComponent();
    }

    private void AddEditSuppliercs_Load(object sender, EventArgs e)
    {
        if (thisSupplier != null)
        {
            txtName.Text = thisSupplier.Name;
            txtEmail.Text = thisSupplier.Email;

            Close();
        }
    }

    private void Okbtn_Click(object sender, EventArgs e)
    {
        if (thisSupplier != null)
        {
            thisSupplier.Name = txtName.Text;
            thisSupplier.Email = txtEmail.Text;

            Close();
        }
    }
}

问题原因与修复方案 #

问题根源 #

窗体闪退的直接原因是AddEditSuppliercs_Load方法里的Close()调用：
当你点击添加供应商按钮时，主窗体会创建一个新的Supplier实例并赋值给addEditSuppliercs.thisSupplier，导致窗体加载时触发if (thisSupplier != null)分支，直接调用Close()关闭窗体。

修复步骤 #

1. 移除加载事件里的关闭代码
   修改AddEditSuppliercs_Load方法，删除多余的Close()，这个方法的作用是编辑已有供应商时填充数据，添加场景下不需要关闭窗体：

private void AddEditSuppliercs_Load(object sender, EventArgs e)
{
    if (thisSupplier != null)
    {
        txtName.Text = thisSupplier.Name;
        txtEmail.Text = thisSupplier.Email;
        // 移除Close()调用
    }
}

2. 设置确认按钮的DialogResult
   在Okbtn_Click方法里，关闭窗体前需要设置DialogResult.OK，这样主窗体才能识别用户是确认添加，进而执行后续的添加和刷新操作：

private void Okbtn_Click(object sender, EventArgs e)
{
    if (thisSupplier != null)
    {
        thisSupplier.Name = txtName.Text;
        thisSupplier.Email = txtEmail.Text;

        DialogResult = DialogResult.OK; // 添加此行
        Close();
    }
}

3. 检查商品添加窗体
   同理，检查你的AddEditContract窗体是否存在同样的问题，确保添加商品时窗体也能正常工作。

修改完成后，点击添加供应商按钮，窗体就能正常打开，用户输入信息后点击确认，主窗体就会将新供应商添加到列表并刷新显示。

内容的提问来源于stack exchange，提问作者AlexArd21