实现:
一、绑定数据库
点击查询按钮,comboBox显示从数据库查到的某字段的一列数据
方法:在按钮的点击事件绑定数据库
private void button1_Click(object sender, EventArgs e){using (SQLiteConnection con = new SQLiteConnection(Constants.DATA_SOURCE)){con.Open();using (SQLiteCommand cmd = new SQLiteCommand()){cmd.Connection = con;cmd.CommandText = string.Format("select * from test t");int rows = cmd.ExecuteNonQuery();SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);DataSet ds = new DataSet();sda.Fill(ds);//con.Close();DataTable dt = ds.Tables[0];this.comboBox1.DataSource = dt;this.comboBox1.DisplayMember="name"; //要显示的数据库中某字段的一列数据this.comboBox1.ValueMember = "id"; //设置了ValueMember=‘id’}}}
设置了ValueMember=‘id’,然后前台页面就可以根据comboBox选中的项,获取其id,
根据选中的comboBox的项获取其id值:string str=comboBox1.SelectedValue.ToString();
根据选中的comboBox的项获取其文本值:string str=comboBox1.Text;
二、模糊查询(在上面代码的基础上加两句)
在comboBox上输入的字传给str,sql语句模糊查询这个str即可
string str = this.comboBox1.Text;using (SQLiteConnection con = new SQLiteConnection(Constants.DATA_SOURCE)){con.Open();using (SQLiteCommand cmd = new SQLiteCommand()){cmd.Connection = con;cmd.CommandText = string.Format("select * from test t where t.name like '%"+str+"%'");int rows = cmd.ExecuteNonQuery();SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);DataSet ds = new DataSet();sda.Fill(ds);//con.Close();DataTable dt = ds.Tables[0];this.comboBox1.DataSource = dt;this.comboBox1.DisplayMember = "name";this.comboBox1.ValueMember = "id";
this.comboBox1.DroppedDown = true; //点击查询,让comboBox下拉列表展开显示得到的结果,
}}
三、自动补全后面剩余字段
需要绑定数据源到Load方法里,而且打开页面就能显示所有数据,
private void Form1_Load(object sender, EventArgs e){using (SQLiteConnection con = new SQLiteConnection(Constants.DATA_SOURCE)){con.Open();using (SQLiteCommand cmd = new SQLiteCommand()){cmd.Connection = con;cmd.CommandText = string.Format("select * from test t");int rows = cmd.ExecuteNonQuery();SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);DataSet ds = new DataSet();sda.Fill(ds);//con.Close();DataTable dt = ds.Tables[0];this.comboBox1.DataSource = dt;this.comboBox1.DisplayMember = "name";this.comboBox1.ValueMember = "id";
this.comboBox1.AutoCompleteMode = AutoCompleteMode.SuggestAppend; //自动补全后面剩余字段this.comboBox1.AutoCompleteSource = AutoCompleteSource.ListItems; //自动补全后面剩余字段
} } }