前端界面操作數據庫
一、思維導圖
二、知識點介紹
前端操作數據要用到的不僅僅是浮現在用戶前面的一堆控件，控件的背后還需要代碼的支持才能真正的做到，運用前端操作數據庫。
首先，我們要連接數據庫：
InitializeComponent(); SqlConnection sqlConnection = new SqlConnection();
sqlConnection.ConnectionString =
"Server=(Local);Database=EMR;Integrated Security=sspi";
sqlConnection.Open();
MessageBox.Show
("連接狀態：" + sqlConnection.State.ToString()
+ "\n工作站標識：" + sqlConnection.WorkstationId
+ "\n服務器地址：" + sqlConnection.DataSource
+ "\n服務器版本：" + sqlConnection.ServerVersion
+ "\n數據庫名稱：" + sqlConnection.Database
+ "\n\n（單擊【確定】后將關閉SQL連接）");
sqlConnection.Close();
MessageBox.Show
("連接狀態：" + sqlConnection.State.ToString());
接着，我們進行注冊：
SqlConnection sqlConnection = new SqlConnection();
sqlConnection.ConnectionString =
ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString;
SqlCommand sqlCommand = new SqlCommand();
sqlCommand.Connection = sqlConnection;
sqlCommand.CommandText ="INSERT 學生 (學號，姓名,班級，電話)
VALUES(@學號，@姓名,@班級，@電話);";
sqlCommand.Parameters.AddWithValue("@學號", cob_學號 .Text.Trim());
sqlCommand.Parameters.AddWithValue("@姓名", cob_姓名 .Text.Trim());
sqlCommand.Parameters.AddWithValue("@班級", cob_班級 .Text.Trim());
sqlCommand.Parameters.AddWithValue("@電話", cob_電話 .Text.Trim());
sqlConnection.Open();
int rowAffected = sqlCommand.ExecuteNonQuery();
sqlConnection.Close();
MessageBox.Show("保存成功");
然后，我們來試驗一下是否可以登錄：
SqlConnection sqlConnection = new SqlConnection();
sqlConnection.ConnectionString =
ConfigurationManager.ConnectionStrings["Sql"].ConnectionString;
SqlCommand sqlCommand = new SqlCommand();
sqlCommand.Connection = sqlConnection; if (button1_Click_1.Checked == true)
{
sqlCommand.CommandText =
"SELECT * FROM EMR WHERE XH=@XH AND Name=@Name;
sqlParameter.ParameterName= "@XH";
sqlParameter.Value = this.textBox1.Text.Trim();
sqlParameter.SqlDbType = SqlDbType.VarChar;
sqlParameter.Size = 20;
sqlCommand.Parameters.Add(sqlParameter);
sqlCommand.Parameters.AddWithValue("@Name", this.textbxpsw.Text.Trim());
sqlCommand.Parameters["@Name"].SqlDbType = SqlDbType.VarChar;
MessageBox.Show("登陸成功","登陸成功");
}