C#谁能帮我解释这个代码每一句语句的意思？

来源：百度知道 编辑：UC知道 时间：2024/06/23 09:27:48
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms; //DataSet-->DataTable-->Rows-->Rows[i][j]

namespace 课室申请管理
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{
string kind = null;
string name = txtname.Text.Trim();
string stu_num = txtsut_num.Text.Trim();
string sqlselect=null;
if (comboBox1.SelectedItem.ToString() == "学生")
{
sqlselect = "select * from student where sno='" + stu_num + "' and sna='" + name + "'";
kind = &quo

//以下七句是声明命名空间
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms; //DataSet-->DataTable-->Rows-->Rows[i][j]

namespace 课室申请管理
{
public partial class Form1 : Form
{
//Form1()构造函数
public Form1()
{
InitializeComponent();
}

//响应单击button1的事件
private void button1_Click(object sender, EventArgs e)
{
string kind = null;
string name = txtname.Text.Trim(); //获取文本框中输入的姓名
string stu_num = txtsut_num.Text.Trim(); //获取文本框中输入的学号
string sqlselect=null; //SQL语句中的SELECT语句，初始化为空
//如果comboBox1中选的是“学生”，则写出SQL中的SELECT语句，按文本框中输入的学号和姓名从student表中选出所要查询的学生信息
if (comboBox1.SelectedItem.ToString() == "学生")
{
sqlselect = "select * from student where sno='" + stu_num + "' and sna='" + n