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DbConnectionStringBuilder.ContainsKey Method

Determines whether the DbConnectionStringBuilder contains a specific key.

Namespace:  System.Data.Common
Assembly:  System.Data (in System.Data.dll)

public virtual bool ContainsKey(
	string keyword


Type: System.String
The key to locate in the DbConnectionStringBuilder.

Return Value

Type: System.Boolean
true if the DbConnectionStringBuilder contains an entry with the specified key; otherwise false.


keyword is a null reference (Nothing in Visual Basic).

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:");

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

This code produces the following output:

Contents of the DbConnectionStringBuilder:
properties="Excel 8.0;HDR=Yes;IMEX=1"
The collection contains the key "Data Source".

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.