DbConnectionStringBuilder.ContainsKey(String) 方法

定義

命名空間:

System.Data.Common

組件:

System.Data.Common.dll

來源:

DbConnectionStringBuilder.cs

判斷 DbConnectionStringBuilder 是否包含特定索引鍵。

public:
 virtual bool ContainsKey(System::String ^ keyword);

public virtual bool ContainsKey (string keyword);

abstract member ContainsKey : string -> bool
override this.ContainsKey : string -> bool

Public Overridable Function ContainsKey (keyword As String) As Boolean

參數

keyword

String

要在 DbConnectionStringBuilder 中尋找的索引鍵。

傳回

Boolean

如果 DbConnectionStringBuilder 包含具有指定索引鍵的項目，則為 true；否則為 false。

例外狀況

ArgumentNullException

keyword 為 null 參考 (在 Visual Basic 中為 Nothing)。

範例

static void Main()
{
    DbConnectionStringBuilder builder = new DbConnectionStringBuilder();
    builder.Add("Provider", "Provider=Microsoft.Jet.OLEDB.4.0");
    builder.Add("Data Source", "C:\\ThisExcelWorkbook.xls");
    builder.Add("Extended Properties", "Excel 8.0;HDR=Yes;IMEX=1");

    // Displays the values in the DbConnectionStringBuilder.
    Console.WriteLine("Contents of the DbConnectionStringBuilder:");
    Console.WriteLine(builder.ConnectionString);

    // Searches for a key.
    if (builder.ContainsKey("Data Source"))
    {
        Console.WriteLine("The collection contains the key \"Data Source\".");
    }
    else
    {
        Console.WriteLine("The collection does not contain the key \"Data Source\".");
    }
    Console.ReadLine();
}

Sub Main()
    ' The following code example searches for an element in a 
    ' DbConnectionStringBuilder.
    Dim builder As New DbConnectionStringBuilder
    builder.Add("Provider", "Provider=Microsoft.Jet.OLEDB.4.0")
    builder.Add("Data Source", "C:\ThisExcelWorkbook.xls")
    builder.Add("Extended Properties", "Excel 8.0;HDR=Yes;IMEX=1")

    ' Displays the values in the DbConnectionStringBuilder.
    Console.WriteLine("Contents of the DbConnectionStringBuilder:")
    Console.WriteLine(builder.ConnectionString)

    ' Searches for a key.
    If builder.ContainsKey("Data Source") Then
        Console.WriteLine("The collection contains the key ""Data Source"".")
    Else
        Console.WriteLine("The collection does not contain the key ""Data Source"".")
    End If
    Console.ReadLine()
End Sub

此程式碼會產生下列輸出：

Contents of the DbConnectionStringBuilder:
provider="Provider=Microsoft.Jet.OLEDB.4.0";data
source=C:\MyExcel.xls;extended
properties="Excel 8.0;HDR=Yes;IMEX=1"
The collection contains the key "Data Source".

另請參閱

• ADO.NET 中的連接字串
• ADO.NET 概觀 \(部分機器翻譯\)