从MS Access数据库中获取数据并显示在列表框中
本文关键字:显示 列表 获取 MS Access 数据库 数据 | 更新日期: 2023-09-27 18:01:25
如何读取ms access数据库中的数据并将其显示在列表框中?我有代码在这里,但我有错误。
private void button3_Click(object sender, EventArgs e)
{
using (OleDbConnection conn = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=''Sisc-stronghold'mis!'wilbert.beltran'DataBase'DataStructure.accdb"))
using(OleDbCommand cmd = new OleDbCommand(" SELECT * from TableAcct", conn))
{
conn.Open();
OleDbDataReader Reader = cmd.ExecuteReader();
//if (Reader.HasRows)
if (Reader.HasRows)
{
Reader.Read();
listBox1.Text = Reader.GetString("FirstName");
}
}
错误如下:1. 最佳重载方法匹配' system . data . common . dbdatareader . getstring (int)'有一些无效参数。2. 错误2参数'1':无法从'string'转换为'int'
试试这个,
List<String> firstName = new List<String>();
List<String> lastName = new List<String>();
private void loadButton_Click(object sender, EventArgs e)
{
cn.Open();
OleDbDataReader reader = null;
cmd = new OleDbCommand("select* from Records", cn);
reader = cmd.ExecuteReader();
while (reader.Read())
{
firstName.Add(reader["FirstName"].ToString());
lastName.Add(reader["LastName"].ToString());
}
cn.Close();
}
然后在你的搜索按钮中插入这个,
private void searchButton_Click(object sender, EventArgs e)
{
clearSearchResult();
try
{
int totalItems = FirstName.Count;
int count = 0;
while (count < totalItems)
{
if (textBox6.Text == FirstName[count].ToString())
{
listBox1.Items.Add(FirstName[count].ToString());
count = 100;
}
else
{
count++;
}
当您想要在listBox1_SelectedIndexChanged
中显示"FirstName"
的信息时,如果您想要,可以使用它。这里有一个例子,
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
int totalItems = lastName.Count;
int count = 0;
while (count < totalItems)
{
if ((listBox1.SelectedItem.ToString()) == firstName[count].ToString()))
{
textBox1.Text = firstName[count].ToString();
textBox2.Text = lastName[count].ToString();
count = 100;
}
else
{
count++;
}
}
希望有帮助,
change
listBox1.Text = Reader.GetString("FirstName");
listBox1.Text = Reader.GetString(0); // zero base ordinal of column
GetString()
的形参是int类型,而不是字符串类型。这意味着您必须使用列的索引。
如果"FirstName"是第二列,则索引为1:
listBox1.Text = Reader.GetString(1);
http://msdn.microsoft.com/en-us/library/system.data.oledb.oledbdatareader.getstring.aspx 使用While循环
while(reader.Read())
{
listbox1.Items.Add(reader["FirstName"]);
}
将遍历所选的所有行。如果没有更多的行,reader.Read()
返回false
。
也:如果你想从列中检索值,我建议你用索引ón reader
实例来做。就像我的例子。
var value = reader["ColumnName"];
与
相比,这增加了可读性var value = reader.GetString(0);
如果你想只显示第一个值-我建议你使用cmd.ExecuteScalar()
和适应你的sql只返回你需要的值:
using(OleDbCommand cmd = new OleDbCommand("SELECT firstname from TableAcct", conn))
{
conn.Open();
var firstName = cmd.ExecuteScalar();
}
请注意,this将给你表中的第一个 "FirstName"。由于没有"order by firstname"
或"where someKey = 1"
-这可能不会返回您期望的结果。
如果你想创建MS Access数据库并访问它,并在某些组件中显示数据,就像这里我将向你展示。如何连接MS Access数据库并在标签中显示数据库中的数据。首先创建任何Access数据库,比如这里的"PirFahimDataBase"。现在在Visual Studio的菜单中输入
- 点击数据
- 添加新数据库
- 单击Next
- 点击新建连接
- 现在通过点击更改来更改数据源,并选择Microsoft Access数据库文件
- 单击Browse选择您创建的数据库
现在在Button ClickEvent中粘贴这些代码,它将从数据库中获取数据并将其显示在标签
中using System.Windows.Forms; //these two lines should be written before namespace at top of the program
using System.Data.OleDb;
private void button1_Click(object sender, EventArgs e)
{
System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection();
conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;" +
@"Data source= C:'Users'pir fahim shah'Documents'PirFahimDataBase.accdb";
try
{
conn.Open();
MessageBox.Show("connected successfuly");
OleDbDataReader reader = null; // This is OleDb Reader
OleDbCommand cmd = new OleDbCommand("select TicketNo from Table1 where Sellprice='6000' ", conn);
reader = cmd.ExecuteReader();
while (reader.Read())
{
label1.Text= reader["TicketNo"].ToString();
}
}
catch (Exception ex)
{
MessageBox.Show("Failed to connect to data source");
}
finally
{
conn.Close();
}
}//end of button click event
您的错误在这一行:
listBox1.Text = Reader.GetString("FirstName");
必须在GetString()
函数中传递一个数字
DataColumn[] PrimaryKeyColumn = new DataColumn[1]; //Define Primary coloumn
DataSet dataSet = new DataSet();
DataTable dataTable = new DataTable();
ReadAndUpdateExcel.ReadExcel(strPath, sheetName, out dataSet);
dataSet.Tables.Add(dataTable);
PrimaryKeyColumn[0] = dataSet.Tables[0].Columns[0];
dataSet.Tables[0].PrimaryKey = PrimaryKeyColumn;
string num = dataSet.Tables[0].Rows[dataSet.Tables[0].Rows.IndexOf(dataSet.Tables[0].Rows.Find(strTCName))]["ACNO"].ToString();
//string country