时间:2020-12-09 21:16:09 | 栏目:.NET代码 | 点击:次
先是查询整张表,用到combobox选择查询哪张表,最后用DataGridView显示
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; namespace WindowsFormsApplication2 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e) { } private void Form1_Load(object sender, EventArgs e) { this.dataGridView1.RowHeadersVisible = false; this.dataGridView1.AllowUserToAddRows = false; this.dataGridView1.ReadOnly = true; this.dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect; // this.comboBox1.SelectedIndex =0; string sql = "select * from student"; DataTable table = SqlManage.TableSelect(sql); this.dataGridView1.DataSource = table; comboBox1.Items.Add("学生表"); comboBox1.Items.Add("教师表"); } private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { string sql = ""; switch (this.comboBox1.SelectedIndex) { case 0: sql = "select id as 学生号,name as 姓名,sage as 年龄 from student"; break; case 1: sql = "select t_id as 教师号,t_name as 姓名,T_age as 年龄 from teacher"; break; default: break; } DataTable table = SqlManage.TableSelect(sql); this.dataGridView1.DataSource = table; } } }
然后是修改表格,这个比较简单,用到textbox和button
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; namespace WindowsFormsApplication2 { public partial class Form2 : Form { public Form2() { InitializeComponent(); } private void button4_Click(object sender, EventArgs e) { this.Close(); } private void button1_Click(object sender, EventArgs e) { string sql = string.Format("insert into teacher values('{0}','{1}','{2}')", this.textBox1.Text, this.textBox2.Text, this.textBox3.Text); SqlManage.TableChange(sql); } private void button2_Click(object sender, EventArgs e) { string sql = string.Format("update teacher set ('{0}',''{1}'','{2}')", this.textBox1.Text, this.textBox2.Text, this.textBox3.Text); SqlManage.TableChange(sql); } private void button3_Click(object sender, EventArgs e) { string sql = string.Format("delete from teacher where t_id='{0}'", this.textBox1.Text); SqlManage.TableChange(sql); } private void Form2_Load(object sender, EventArgs e) { } } }
按条件查询表格,这个是核心,用到radiobutt,combobox,,button, DataGridView
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; namespace WindowsFormsApplication2 { public partial class Form3 : Form { public Form3() { InitializeComponent(); } private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e) { } private void Form3_Load(object sender, EventArgs e) { this.comboBox1.Enabled = false; this.comboBox2.Enabled = false; this.comboBox3.Enabled = false; this.comboBox4.Enabled = false; //初始化教师编号 string sql = "select t_id from teacher"; DataTable table = SqlManage.TableSelect(sql); string t_id; foreach (DataRow row in table.Rows) { t_id = row["t_id"].ToString(); this.comboBox1.Items.Add(t_id); } if (table.Rows.Count > 0) { this.comboBox1.SelectedIndex = 0; } //初始化教师姓名 string sql_name = "select t_name from teacher"; table.Clear(); table = SqlManage.TableSelect(sql_name); string t_name; foreach (DataRow row in table.Rows) { t_name= row["t_name"].ToString(); this.comboBox2.Items.Add(t_name); } if (table.Rows.Count > 0) { this.comboBox2.SelectedIndex = 0; } //初始化学生 string sql_id = "select id from student"; table.Clear(); table = SqlManage.TableSelect(sql_id); string s_id; foreach (DataRow row in table.Rows) { s_id = row["id"].ToString(); this.comboBox3.Items.Add(s_id); } if (table.Rows.Count > 0) { this.comboBox3.SelectedIndex = 0; } //初始化学生 string sql_sname = "select name from student"; table.Clear(); table = SqlManage.TableSelect(sql_sname); string t_sname; foreach (DataRow row in table.Rows) { t_sname = row["name"].ToString(); this.comboBox4.Items.Add(t_sname); } if (table.Rows.Count > 0) { this.comboBox4.SelectedIndex = 0; } } private void button2_Click(object sender, EventArgs e) { this.Close(); } private void button1_Click(object sender, EventArgs e) { string sql = ""; if (this.radioButton1.Checked) { sql = string.Format("select t_id as 教师编号,t_name as 教师姓名,t_age as 年龄 from teacher where t_id = '{0}'", this.comboBox1.Text); } else if (this.radioButton2.Checked) { sql = string.Format("select t_id as 教师编号,t_name as 教师姓名,t_age as 年龄 from teacher where t_name = '{0}'", this.comboBox2.Text); } else if (this.radioButton3.Checked) { sql = string.Format("select id as 学生编号,name as 学生姓名,sage as 年龄 from student where id = '{0}'", this.comboBox3.Text); } else if (this.radioButton4.Checked) { sql = string.Format("select id as 学生编号,name as 学生姓名,sage as 年龄 from student where name = '{0}'", this.comboBox4.Text); } DataTable table = SqlManage.TableSelect(sql); if (table.Rows.Count > 0) { this.dataGridView1.DataSource = table; } else { MessageBox.Show("没有相关内容"); } } private void radioButton1_CheckedChanged(object sender, EventArgs e) { if (this.radioButton1.Checked) { this.comboBox1.Enabled = true; } else { this.comboBox1.Enabled = false; } } private void radioButton2_CheckedChanged(object sender, EventArgs e) { if (this.radioButton2.Checked) { this.comboBox2.Enabled = true; } else { this.comboBox2.Enabled = false; } } private void radioButton3_CheckedChanged(object sender, EventArgs e) { if (this.radioButton3.Checked) { this.comboBox3.Enabled = true; } else { this.comboBox3.Enabled = false; } } private void radioButton4_CheckedChanged(object sender, EventArgs e) { if (this.radioButton4.Checked) { this.comboBox4.Enabled = true; } else { this.comboBox4.Enabled = false; } } } }