[英]How to check if connection string is valid?
我正在编写一个应用程序,其中用户手动提供连接字符串,我想知道是否有任何方法可以验证连接字符串 - 我的意思是检查它是否正确以及数据库是否存在。
You could try to connect?你可以尝试连接吗? For quick (offline) validation, perhaps use
DbConnectionStringBuilder
to parse it...为了快速(离线)验证,也许使用
DbConnectionStringBuilder
来解析它......
DbConnectionStringBuilder csb = new DbConnectionStringBuilder();
csb.ConnectionString = "rubb ish"; // throws
But to check whether the db exists, you'll need to try to connect.但是要检查数据库是否存在,您需要尝试连接。 Simplest if you know the provider, of course:
当然,如果您知道提供者,则最简单:
using(SqlConnection conn = new SqlConnection(cs)) {
conn.Open(); // throws if invalid
}
If you only know the provider as a string (at runtime), then use DbProviderFactories
:如果您只知道提供者作为字符串(在运行时),则使用
DbProviderFactories
:
string provider = "System.Data.SqlClient"; // for example
DbProviderFactory factory = DbProviderFactories.GetFactory(provider);
using(DbConnection conn = factory.CreateConnection()) {
conn.ConnectionString = cs;
conn.Open();
}
Try this.试试这个。
try
{
using(var connection = new OleDbConnection(connectionString)) {
connection.Open();
return true;
}
}
catch {
return false;
}
If the goal is validity and not existence, the following will do the trick:如果目标是有效性而不是存在,则以下内容将起作用:
try
{
var conn = new SqlConnection(TxtConnection.Text);
}
catch (Exception)
{
return false;
}
return true;
For sqlite use this: Suppose you have connection string in textbox txtConnSqlite对于 sqlite 使用这个:假设你在文本框 txtConnSqlite 中有连接字符串
Using conn As New System.Data.SQLite.SQLiteConnection(txtConnSqlite.Text)
Dim FirstIndex As Int32 = txtConnSqlite.Text.IndexOf("Data Source=")
If FirstIndex = -1 Then MsgBox("ConnectionString is incorrect", MsgBoxStyle.Exclamation, "Sqlite") : Exit Sub
Dim SecondIndex As Int32 = txtConnSqlite.Text.IndexOf("Version=")
If SecondIndex = -1 Then MsgBox("ConnectionString is incorrect", MsgBoxStyle.Exclamation, "Sqlite") : Exit Sub
Dim FilePath As String = txtConnSqlite.Text.Substring(FirstIndex + 12, SecondIndex - FirstIndex - 13)
If Not IO.File.Exists(FilePath) Then MsgBox("Database file not found", MsgBoxStyle.Exclamation, "Sqlite") : Exit Sub
Try
conn.Open()
Dim cmd As New System.Data.SQLite.SQLiteCommand("SELECT * FROM sqlite_master WHERE type='table';", conn)
Dim reader As System.Data.SQLite.SQLiteDataReader
cmd.ExecuteReader()
MsgBox("Success", MsgBoxStyle.Information, "Sqlite")
Catch ex As Exception
MsgBox("Connection fail", MsgBoxStyle.Exclamation, "Sqlite")
End Try
End Using
I think you can easilly convert it to c# code我认为您可以轻松地将其转换为 C# 代码
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