using?System;
using?System.Threading;
using?System.Data.SqlClient;
using?System.Windows.Forms;

namespace?exp4
{
????public?partial?class?Form1?:?Form
????{
????????SqlDataReader?sqlReader?=?null;

????????public?Form1（）
????????{
????????????InitializeComponent（）;
????????????this.MaximizeBox?=?false;
????????????this.MinimizeBox?=?false;
????????????this.AutoSizeMode?=?AutoSizeMode.GrowAndShrink;
????????}

????????private?void?button1_Click（object?sender?EventArgs?e）
????????{
????????????checkLogin（）;
????????}

????????private?void?checkLogin（）
????????{
????????????string?connStr?=?@“Data?Source=（LocalDB）\MSSQLLocalDB;AttachDbFilename=E:\Desktop\C-Sharp\Month_12\exp4\exp4\DB\userInfo.mdf;Integrated?Security=True“;
????????????SqlConnection?conn?=?new?SqlConnection（connStr）;

????????????string?rawUsername?=?usernameTextBox.Text.Trim（）;
????????????string?rawPassword?=?passwordTextBox.Text.Trim（）;

????????????//數(shù)據(jù)庫連接
????????????try
????????????{
????????????????conn.Open（）;
????????????????string?sql1?=?$“SELECT?*?FROM?[dbo].[User]?WHERE?userName?=?‘{rawUsername}‘“;
????????????????var?command?=?new?SqlCommand（sql1?conn）;
????????????????sqlReader?=?command.ExecuteReader（）;
????????????????if?（!sqlReader.Read（））
????????????????{
????????????????????MessageBox.Show（“賬戶不存在！“?“登錄提示！“）;
????????????????}
????????????????else?if?（sqlReader.GetString（1）?!=?rawPassword）
????????????????{
????????????????????MessageBox.Show（“密碼錯(cuò)誤！“?“登錄提示！“）;
????????????????}
????????????????else
????????????????{
????????????????????MessageBox.Show（“登錄成功!正在跳轉(zhuǎn)...“?“登錄提示！“）;
????????????????????//this.Hide（）;
????????????????????//new?Form2（）.Show（）;????//ShowDialog會使得窗口固定大小屬性失效！
????????????????????Program.signal?=?true;
????????????????????this.Close（）;
????????????????}
????????????}
????????????catch（Exception?ex）
????????????{
????????????????MessageBox.Show（ex.Message?“錯(cuò)誤提示！“）;
????????????}
????????????finally
????????????{
????????????????sqlReader.Close（）;
????????????????conn.Close（）;
????????????}
????????}
????}
}

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2019-12-10?11:49??exp4\
?????目錄???????????0??2019-12-10?11:49??exp4\.vs\
?????目錄???????????0??2019-12-10?11:49??exp4\.vs\exp4\
?????目錄???????????0??2019-12-10?11:49??exp4\.vs\exp4\v15\
?????文件???????41984??2019-12-10?22:42??exp4\.vs\exp4\v15\.suo
?????目錄???????????0??2019-12-10?11:49??exp4\.vs\exp4\v15\Server\
?????目錄???????????0??2019-12-10?11:49??exp4\.vs\exp4\v15\Server\sqlite3\
?????文件???????????0??2019-12-10?11:49??exp4\.vs\exp4\v15\Server\sqlite3\db.lock
?????文件??????593920??2019-12-10?20:28??exp4\.vs\exp4\v15\Server\sqlite3\storage.ide
?????文件???????32768??2019-12-10?21:41??exp4\.vs\exp4\v15\Server\sqlite3\storage.ide-shm
?????文件?????4128272??2019-12-10?22:41??exp4\.vs\exp4\v15\Server\sqlite3\storage.ide-wal
?????目錄???????????0??2019-12-10?22:42??exp4\exp4\
?????文件????????1110??2019-12-10?11:49??exp4\exp4.sln
?????文件?????????189??2019-12-10?11:49??exp4\exp4\App.config
?????目錄???????????0??2019-12-10?12:07??exp4\exp4\DB\
?????文件?????8388608??2019-12-10?22:42??exp4\exp4\DB\userInfo.mdf
?????文件?????8388608??2019-12-10?22:42??exp4\exp4\DB\userInfo_log.ldf
?????文件????????5510??2019-12-10?13:33??exp4\exp4\exp4.csproj
?????文件?????????453??2019-12-10?12:23??exp4\exp4\exp4.csproj.user
?????文件????????2237??2019-12-10?22:41??exp4\exp4\Form1.cs
?????文件????????5820??2019-12-10?13:33??exp4\exp4\Form1.Designer.cs
?????文件????????5817??2019-12-10?13:33??exp4\exp4\Form1.resx
?????文件???????12423??2019-12-10?22:41??exp4\exp4\Form2.cs
?????文件????????8557??2019-12-10?20:29??exp4\exp4\Form2.Designer.cs
?????文件????????5817??2019-12-10?20:29??exp4\exp4\Form2.resx
?????目錄???????????0??2019-12-10?11:49??exp4\exp4\obj\
?????目錄???????????0??2019-12-10?20:54??exp4\exp4\obj\Debug\
?????文件????????1443??2019-12-10?20:54??exp4\exp4\obj\Debug\DesignTimeResolveAssemblyReferences.cache
?????文件????????7331??2019-12-10?13:12??exp4\exp4\obj\Debug\DesignTimeResolveAssemblyReferencesInput.cache
?????文件??????????42??2019-12-10?13:12??exp4\exp4\obj\Debug\exp4.csproj.CoreCompileInputs.cache
?????文件?????????909??2019-12-10?21:28??exp4\exp4\obj\Debug\exp4.csproj.FileListAbsolute.txt
............此處省略21個(gè)文件信息