数组：
using System;
class Test
{
static void Main()
{
int[] tmep = new int[5];
for (int i = 0; i<temp.Length; i++)
Console.WriteLine("tem[{0}] = {1}", i, tem[i]);
}}
引用传参：
using System;
class Test
{
static void Swap(ref int a, ref int b){
int t = a;
a = b;
b = t;
}
static void Main()
{
int x =1, y =2;//必须进行初始化，如果用out 就不需要
Swap(ref x, ref y);
}
}
两种连接sqlserver的方法
SQLConnection
String connectionString = "server=localhost;uid=sa;pwd=;database=northwind";
SQLConnection myConn=new SQLConnection(connectionString);
myConn.Open;
ADOConnection
String connectionString = "Provider=SQLOLEDB.1;Data Source=localhost;uid=sa;pwd=;Initial Catalog=northwind";
ADOConnection myConn=new ADOConnection(connectionString);
myConn.Open;
访问Access数据库
将此行添加到 WebForm1.aspx.cs 开始处的 using 语句 using System.Data.OleDb;
将此代码插入到 Page_Load 方法：
private void Page_Load(object sender, System.EventArgs e)
{
if (!IsPostBack) ReadRecords();
}
将 ReadRecords 方法添加到紧接在 Page_Load 方法之后的 PetForm 类：
private void ReadRecords()
{
OleDbConnection conn = null;
OleDbDataReader reader = null;
try
{
conn = new OleDbConnection(
"Provider=Microsoft.Jet.OLEDB.4.0; "
"Data Source=" Server.MapPath("Pets/Pets.mdb"));
conn.Open();
OleDbCommand cmd =
new OleDbCommand("Select * FROM PetTable", conn);
reader = cmd.ExecuteReader();
datagrid.DataSource = reader;
datagrid.DataBind();
}
// catch (Exception e)
// {
// Response.Write(e.Message);
// Response.End();
// }
finally
{
if (reader != null) reader.Close();
if (conn != null) conn.Close();
}
}
访问Excel数据库
将下面的语句添加到代码隐藏页顶部的命名空间部分之上：
using System.Data.OleDb;
using System.Data;
在 WebForm1.aspx.cs 中，将这些代码复制到 Page_Load 事件中：
// Create connection string variable. Modify the "Data Source"
// parameter as appropriate for your environment.
String sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;"
"Data Source=" Server.MapPath("../ExcelData.xls") ";"
"Extended Properties=Excel 8.0;";
// Create connection object by using the preceding connection string.
OleDbConnection objConn = new OleDbConnection(sConnectionString);
// Open connection with the database.
objConn.Open();
// The code to follow uses a SQL SELECT command to display the data from the worksheet.
// Create new OleDbCommand to return data from worksheet.
OleDbCommand objCmdSelect =new OleDbCommand("SELECT * FROM myRange1", objConn);
// Create new OleDbDataAdapter that is used to build a DataSet
// based on the preceding SQL SELECT statement.
OleDbDataAdapter objAdapter1 = new OleDbDataAdapter();
// Pass the Select command to the adapter.
objAdapter1.SelectCommand = objCmdSelect;
// Create new DataSet to hold information from the worksheet.
DataSet objDataset1 = new DataSet();
// Fill the DataSet with the information from the worksheet.
objAdapter1.Fill(objDataset1, "XLData");
// Bind data to DataGrid control.
DataGrid1.DataSource = objDataset1.Tables[0].DefaultView;
DataGrid1.DataBind();
// Clean up objects.
objConn.Close();