Question

在以下代码中：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SQLite;
using System.Diagnostics;

namespace WindowsFormsApplication1
{
    public partial class List : Form
    {
        public List()
        {
            InitializeComponent();
        }

        private void List_Load(object sender, EventArgs e)
        {
            comboBox1.SelectedIndex = 1;
        }

        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            var cmd = new SQLiteCommand("select * from students", DB.Connection);
            var ad = new SQLiteDataAdapter(cmd);
            var dt = new DataTable();
            ad.Fill(dt);
            listBox1.DataSource = dt;
            listBox1.DisplayMember = "name";
        }

        private void btnAdd_Click(object sender, EventArgs e)
        {
            Debug.Assert(listBox1.DataSource is DataTable);
            var dt = listBox1.DataSource as DataTable;
            dt.Rows.Add();
            btnEdit.Enabled = btnRemove.Enabled = dt.Rows.Count != 0;
        }

        private void btnEdit_Click(object sender, EventArgs e)
        {
            Debug.Assert(listBox1.SelectedItem is DataRowView);
            new StudentsForm2(listBox1.SelectedItem as DataRowView).ShowDialog(this);
        }

        private void btnRemove_Click(object sender, EventArgs e)
        {
            Debug.Assert(listBox1.DataSource is DataTable);
            var dt = listBox1.DataSource as DataTable;
            dt.Rows.RemoveAt(listBox1.SelectedIndex);
            btnEdit.Enabled = btnRemove.Enabled = dt.Rows.Count != 0;
        }

        private void List_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Escape)
            {
                Close();
            }
        }

    }
}

表为空时，出现以下异常：

System.Windows.Forms.dll中发生了类型'System.ArgumentOutOfRangeException'的第一次机会异常

其他信息：InvalidArgument =值“ 0”对于“ SelectedIndex”无效。

在btnAdd_Click方法中的

调用dt.Rows.Add（）时。 comboBox1保存表名，但是由于我目前只有一个表，除非要调用comboBox1_SelectedIndexChanged，否则它将不使用。

这是抛出异常时的堆栈跟踪：

在System.Environment.GetStackTrace（异常e，布尔的NeedFileInfo）在System.Environment.get_StackTrace（）在System.Windows.Forms.ListBox.set_SelectedIndex（Int32值）在System.Windows.Forms.ListControl.DataManager_PositionChanged（对象发送者，EventArgs e）在System.Windows.Forms.CurrencyManager.OnPositionChanged（EventArgs e）在System.Windows.Forms.CurrencyManager.ChangeRecordState（Int32 newPosition，布尔验证，布尔endCurrentEdit，布尔firePositionChange，布尔pullData）在System.Windows.Forms.CurrencyManager.List_ListChanged（对象发送者，ListChangedEventArgs e）在System.Data.DataView.OnListChanged（ListChangedEventArgs e）在System.Data.DataView.IndexListChanged（对象发送者，ListChangedEventArgs e）在System.Data.DataView.IndexListChangedInternal（ListChangedEventArgs e）在System.Data.DataViewListener.IndexListChanged（ListChangedEventArgs e）在System.Data.Index。<> c.b__88_0（DataViewListener侦听器，ListChangedEventArgs args，布尔arg2，布尔arg3）在System.Data.Listeners 1.Notify[T1,T2,T3](T1 arg1, T2 arg2, T3 arg3, Action 4操作）在System.Data.Index.OnListChanged（ListChangedEventArgs e）在System.Data.Index.OnListChanged（ListChangedType更改类型，Int32索引）在System.Data.Index.InsertRecord（Int32记录，布尔型FireEvent）在System.Data.Index.ApplyChangeAction（Int32记录，Int32动作，Int32 changeRecord）在System.Data.Index.RecordStateChanged（Int32记录，DataViewRowState oldState，DataViewRowState newState）在System.Data.DataTable.RecordStateChanged（Int32 record1，DataViewRowState oldState1，DataViewRowState newState1，Int32 record2，DataViewRowState oldState2，DataViewRowState newState2）在System.Data.DataTable.SetNewRecordWorker处（DataRow行，Int32建议的记录，DataRowAction操作，布尔值isInMerge，布尔值detectEnsurePropertyChanged，Int32位置，布尔值fireEvent，Exception＆deferredException）在System.Data.DataTable.InsertRow（DataRow行，Int64提议的ID，Int32 pos，布尔型fireEvent）在System.Data.DataRowCollection.Add（Object []值）在WindowsFormsApplication1.List.btnAdd_Click（Object sender，EventArgs e）中的C：\ Users \ hamidi \ Documents \ Visual Studio 2010 \ Projects \ m_rezaee \ WindowsFormsApplication1 \ WindowsFormsApplication1 \ List.cs：line 44 在System.Windows.Forms.Control.OnClick（EventArgs e）在System.Windows.Forms.Button.OnClick（EventArgs e）在System.Windows.Forms.Button.OnMouseUp（MouseEventArgs mevent）在System.Windows.Forms.Control.WmMouseUp上（消息和m，MouseButtons按钮，Int32单击）在System.Windows.Forms.Control.WndProc（Message＆m）在System.Windows.Forms.ButtonBase.WndProc（Message＆m）在System.Windows.Forms.Button.WndProc（Message＆m）在System.Windows.Forms.Control.ControlNativeWindow.OnMessage（Message＆m）在System.Windows.Forms.Control.ControlNativeWindow.WndProc（Message＆m）在System.Windows.Forms.NativeWindow.DebuggableCallback（IntPtr hWnd，Int32 msg，IntPtr wparam，IntPtr lparam）在System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW（MSG＆msg）在System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop（IntPtr dwComponentID，Int32原因，Int32 pvLoopData）在System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner（Int32原因，ApplicationContext上下文）在System.Windows.Forms.Application.ThreadContext.RunMessageLoop（Int32原因，ApplicationContext上下文）在System.Windows.Forms.Application.Run（Form mainForm）在WindowsFormsApplication1.Program.Main（）中的C：\ Users \ hamidi \ Documents \ Visual Studio 2010 \ Projects \ m_rezaee \ WindowsFormsApplication1 \ WindowsFormsApplication1 \ Program.cs：line 18 在System.AppDomain._nExecuteAssembly（RuntimeAssembly程序集，String []参数）在System.AppDomain.ExecuteAssembly（String assemblyFile，Evidence assemblySecurity，String [] args）中在Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly（）在System.Threading.ThreadHelper.ThreadStart_Context（对象状态）在System.Threading.ExecutionContext.RunInternal（ExecutionContext executeContext，ContextCallback回调，对象状态，布尔类型saveSyncCtx）在System.Threading.ExecutionContext.Run（ExecutionContext执行上下文，ContextCallback回调，对象状态，布尔类型saveSyncCtx）在System.Threading.ExecutionContext.Run（ExecutionContext执行上下文，ContextCallback回调，对象状态）在System.Threading.ThreadHelper.ThreadStart（）

我找不到有关其发生原因的任何线索。

当我调用DataRowCollection.Add

0 个答案: