我在C#中添加了MySQL服务器的引用。我以为我的代码是正确的。我知道连接值适合测试。这是我的错误:
{"建立与SQL Server的连接时发生与网络相关或特定于实例的错误。服务器未找到或无法访问。验证实例名称是否正确,以及SQL Server是否配置为允许远程连接。 (提供者:命名管道提供程序,错误:40 - 无法打开与SQL Server的连接)"}
我的WPF文本框和按钮:
<TextBox x:Name="textError" HorizontalAlignment="Left" Height="35" Margin="125,39,0,0" TextWrapping="Wrap" Text="If Error this will show it" VerticalAlignment="Top" Width="240"/>
<TextBox x:Name="textUser" HorizontalAlignment="Left" Height="23" Margin="125,118,0,0" TextWrapping="Wrap" Text="Username" VerticalAlignment="Top" Width="120"/>
<TextBox x:Name="textPassword" HorizontalAlignment="Left" Height="23" Margin="125,168,0,0" TextWrapping="Wrap" Text="Password" VerticalAlignment="Top" Width="120"/>
我的C#代码:
namespace namespace1
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private MySqlConnection connection;
private string server;
private string database;
private string uid;
private string password;
private void button_Click(object sender, RoutedEventArgs e)
{
if (textUser.Text != "" & textPassword.Text != "")
{
server = "localhost";
database = "test";
uid = "username";
password = "password";
string connectionString;
connectionString = "SERVER=" + server + ";" + "DATABASE=" + database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";";
connection = new MySqlConnection(connectionString);
string queryText = @"SELECT Count(*) FROM Table1
WHERE username = @Username AND password = @Password";
using (SqlConnection cn = new SqlConnection(connectionString))
using (SqlCommand cmd = new SqlCommand(queryText, cn))
{
cn.Open();
cmd.Parameters.AddWithValue("@Username", textUser.Text);
cmd.Parameters.AddWithValue("@Password", textPassword.Text);
int result = (int)cmd.ExecuteScalar();
if (result > 0)
MessageBox.Show("Logged In!");
else
MessageBox.Show("User Not Found!");
}
}
}
}
}
答案 0 :(得分:1)
访问名为Download Connector/Net的MySQL下载页面并继续显而易见。注意找出最近的下载,因为它会老化。
使用适当的 MySQL类。
using MySql.Data.MySqlClient;
string connString = @"server=localhost;userid=drew;password=OpenSesame;database=stackoverflow";
long lRet = 0;
using (MySqlConnection lconn = new MySqlConnection(connString))
{
lconn.Open();
using (MySqlCommand cmd = new MySqlCommand())
{
cmd.Connection = lconn;
cmd.CommandText = @"select count(*) as theCount from batchQMetricsToUpdate where status=1";
lRet = (long)cmd.ExecuteScalar();
}
}
return(lRet);
添加参考资料截图:
答案 1 :(得分:0)
你可以这样做:
document.getElementsByClassName("showMoreNew")[0].click();
要获取完整的代码列表:
using(SqlConnection connection = new MySqlConnection(connectionString))
{
try
{
conn.Open();
}
catch(SqlException ex)
{
switch(ex.Number)
{
case 18456: // Can't login
// Do something
break;
default:
break;
}
}
}