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DbConnectionStringBuilder.ContainsKey(String) Method

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Definition

Namespace:
System.Data.Common
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll
Source:
DbConnectionStringBuilder.cs
Source:
DbConnectionStringBuilder.cs
Source:
DbConnectionStringBuilder.cs

Determines whether the DbConnectionStringBuilder contains a specific key.

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

Parameters

keyword
String

The key to locate in the DbConnectionStringBuilder.

Returns

Boolean

true if the DbConnectionStringBuilder contains an entry with the specified key; otherwise false.

Exceptions

ArgumentNullException

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

Examples

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

This code produces the following output:

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".

Applies to

See also