我正在用数据库创建一个UWP应用程序。 由于某种原因，它将无法连接到本地数据库
我已经安装了MySql.data以供参考，并且确实测试了连接 我还检查以确保远程注册表正在运行
{
string connectString = "server=127.0.0.1;database=harteliefie;Uid=root@localhost;Pwd=;";
string sql = "SELECT * FROM `user`";
private DataTable dataTable;
public MainPage()
{
this.InitializeComponent();
CoreApplication.GetCurrentView().TitleBar.ExtendViewIntoTitleBar = true;
var titleBar = ApplicationView.GetForCurrentView().TitleBar;
if (titleBar != null)
{
titleBar.ButtonBackgroundColor = Colors.Transparent;
titleBar.ButtonInactiveBackgroundColor = Colors.Transparent;
titleBar.ButtonForegroundColor = Colors.DarkSlateGray;
}
}
private async void ConnectButton_Click(object sender, RoutedEventArgs e)
{
try
{
using (SqlConnection connection = new SqlConnection(connectString))
{
connection.Open();
}
var dialog = new MessageDialog("Connected")
{
Title = "OK"
};
await dialog.ShowAsync();
}
catch (Exception ex)
{
var dialog = new MessageDialog(ex.Message)
{
Title = "Error"
};
await dialog.ShowAsync();
}
}
private void Query1Button_Click(object sender, RoutedEventArgs e)
{
var query = @"
SELECT Replace(Lower(type_desc), '_', ' ') AS [Object Type], COUNT(*) AS [Number Of Entities]
FROM sys.objects
WHERE type_desc NOT IN ('SYSTEM_TABLE', 'INTERNAL_TABLE')
GROUP BY type_desc";
ExecuteQuery(query);
}
private void Query2Button_Click(object sender, RoutedEventArgs e)
{
var query = @"
WITH cte AS
(
SELECT DISTINCT fk.constraint_object_id, 0 AS ccid, CONVERT(NVARCHAR(MAX), '') AS cs
FROM sys.foreign_key_columns fk
LEFT OUTER JOIN sys.index_columns ic
ON ic.object_id = fk.parent_object_id /* same table */
AND ic.column_id = fk.parent_column_id /* same column */
AND ic.index_column_id = fk.constraint_column_id /* same column position */
WHERE ic.object_id IS NULL
UNION ALL
SELECT cte.constraint_object_id, fk.constraint_column_id, cte.cs + ', ' + fc.name
FROM cte
JOIN sys.foreign_key_columns fk ON cte.constraint_object_id = fk.constraint_object_id AND cte.ccid + 1 = fk.constraint_column_id
JOIN sys.columns fc ON fk.parent_object_id = fc.object_id AND fk.parent_column_id = fc.column_id
)
SELECT MAX(fks.name) AS [Schema], MAX(fkt.name) AS [Table], SUBSTRING(MAX(cs), 2, 9999999) AS [Columns], MAX(fko.name) AS [Foreign Key], MAX(fkrs.name) AS [Referenced Schema], MAX(fkr.name) AS [Referenced Table]
FROM cte
JOIN sys.foreign_key_columns fk ON cte.constraint_object_id = fk.constraint_object_id AND cte.ccid = fk.constraint_column_id
JOIN sys.objects fkt ON fk.parent_object_id = fkt.object_id
JOIN sys.schemas fks ON fks.schema_id = fkt.schema_id
JOIN sys.objects fko ON fk.constraint_object_id = fko.object_id
JOIN sys.objects fkr ON fk.referenced_object_id = fkr.object_id
JOIN sys.schemas fkrs ON fkr.schema_id = fkrs.schema_id
GROUP BY cte.constraint_object_id";
ExecuteQuery(query);
}
private void Query3Button_Click(object sender, RoutedEventArgs e)
{
var query = @"
SELECT TOP 15
SUM(query_stats.total_worker_time) / SUM(query_stats.execution_count) AS 'Avg CPU Time',
MIN(query_stats.statement_text) AS 'SQL Statement',
MIN(query_stats.statement_text) AS 'Full SQL Statement'
FROM
(SELECT QS.*,
SUBSTRING(ST.text, (QS.statement_start_offset / 2) + 1,
((CASE statement_end_offset
WHEN - 1 THEN DATALENGTH(ST.text)
ELSE QS.statement_end_offset END
- QS.statement_start_offset) / 2) + 1) AS statement_text
FROM sys.dm_exec_query_stats AS QS
CROSS APPLY sys.dm_exec_sql_text(QS.sql_handle) as ST) as query_stats
GROUP BY query_stats.query_hash
ORDER BY 1 DESC;";
ExecuteQuery(query);
}
private async void ExecuteQuery(string query)
{
using (var connection = new SqlConnection(connectString))
{
await connection.OpenAsync();
var command = connection.CreateCommand();
command.CommandText = query;
dataTable = new DataTable();
using (var dataAdapter = new SqlDataAdapter(command))
{
dataAdapter.Fill(dataTable);
}
}
BindTable(dataTable, ResultsGrid);
if (dataTable.Rows.Count == 0)
{
ResultsGrid.Visibility = Visibility.Collapsed;
}
else
{
ResultsGrid.Visibility = Visibility.Visible;
}
}
private void BindTable(DataTable table, DataGrid grid)
{
// Generate columns with index binding
grid.Columns.Clear();
grid.RowDetailsVisibilityMode = DataGridRowDetailsVisibilityMode.Collapsed;
for (int i = 0; i < table.Columns.Count; i++)
{
if (table.Columns[i].ColumnName == "Full SQL Statement")
{
// Treat 'Full SQL Statement' column differently.
grid.RowDetailsVisibilityMode = DataGridRowDetailsVisibilityMode.VisibleWhenSelected;
}
else
{
grid.Columns.Add(new DataGridTextColumn()
{
Header = table.Columns[i].ColumnName,
Binding = new Binding { Path = new PropertyPath("[" + i.ToString() + "]") }
});
}
}
// Post-process 'SQL Statement' column.
if (table.Columns.Contains("SQL Statement"))
{
var column = table.Columns["SQL Statement"];
foreach (DataRow row in table.Rows)
{
string sqlStatement = ((row[column] as string) ?? string.Empty).Trim();
row[column] = string.Join(' ', sqlStatement.Split(default(string[]), StringSplitOptions.RemoveEmptyEntries)).Substring(0, 80) + "...";
}
table.AcceptChanges();
}
RefreshContents(table, grid);
}
private void RefreshContents(DataTable table, DataGrid grid)
{
// Create collection
var collection = new ObservableCollection<object>();
foreach (DataRow row in table.Rows)
{
collection.Add(row.ItemArray);
}
grid.ItemsSource = collection;
}
private void ResultsGrid_Sorting(object sender, DataGridColumnEventArgs e)
{
var currentSortDirection = e.Column.SortDirection;
foreach (var column in ResultsGrid.Columns)
{
column.SortDirection = null;
}
var sortOrder = "ASC";
if ((currentSortDirection == null || currentSortDirection == DataGridSortDirection.Descending))
{
e.Column.SortDirection = DataGridSortDirection.Ascending;
}
else
{
sortOrder = "DESC";
e.Column.SortDirection = DataGridSortDirection.Descending;
}
var dataView = dataTable.DefaultView;
dataView.Sort = e.Column.Header + " " + sortOrder;
dataTable = dataView.ToTable();
RefreshContents(dataTable, ResultsGrid);
}}}
错误是：
ExtendedSocketException：无法建立连接，因为 目标机器主动拒绝它127.0.0.1:1433
System.Data.SqlClient.SqlException：与网络相关或 建立与以下对象的连接时发生特定于实例的错误 SQL Server。服务器未找到或无法访问。校验 实例名称正确并且已将SQL Server配置为 允许远程连接。 （提供者：TCP提供程序，错误：35-An 内部异常被捕获）'
我只需要建立一个成功的连接
答案 0 :(得分：1)
如果使用的是MySql，请使用MySqlConnection（）初始化数据库，例如：
using(MySqlConnection connection = new MySqlConnection(connectString))
{
// other code
}
最诚挚的问候。