IWMPQuery::addCondition method
The addCondition method adds a condition to the compound query using AND logic.
Syntax
public void addCondition(
System.String bstrAttribute,
System.String bstrOperator,
System.String bstrValue
);
Public Sub addCondition( _
ByVal bstrAttribute As System.String, _
ByVal bstrOperator As System.String, _
ByVal bstrValue As System.String _
)
Implements IWMPQuery.addCondition
Parameters
-
bstrAttribute [in]
-
A System.String that is the name of the attribute to be added to the query.
-
bstrOperator [in]
-
A System.String that is the operator. See Remarks for supported values.
-
bstrValue [in]
-
A System.String that is the attribute value.
Return value
This method does not return a value.
Remarks
Conditions contained in a compound query are organized into condition groups. Multiple conditions within a condition group are always concatenated by using AND logic. Condition groups are always concatenated to each other by using OR logic. To start a new condition group, call IWMPQuery.beginNextGroup.
Compound queries using IWMPQuery are not case sensitive.
A list of values for the bstrAttribute parameter can be found in Alphabetical Attribute Reference.
The following table lists the supported values for bstrOperator.
| String | Applies to |
|---|---|
| BeginsWith | Strings |
| Contains | Strings |
| Equals | All types |
| GreaterThan | Numbers, Dates |
| GreaterThanOrEquals | Numbers, Dates |
| LessThan | Numbers, Dates |
| LessThanOrEquals | Numbers, Dates |
| NotBeginsWith | Strings |
| NotContains | Strings |
| NotEquals | All types |
Examples
The following example creates a query, adds two conditions to it, and uses that query to extract the results of the query as a string collection. The results are then displayed in a list box. The AxWMPLib.AxWindowsMediaPlayer object is represented by the variable named player.
// Get a new Query interface.
WMPLib.IWMPMediaCollection2 mc = (WMPLib.IWMPMediaCollection2)player.mediaCollection;
WMPLib.IWMPQuery q = mc.createQuery();
// Add two conditions to the Query.
q.addCondition("WM/Composer", "Equals", "Antonio Vivaldi");
q.addCondition("Title", "Contains", "Trio");
// Query the media collection and get a string collection containing the result.
// In this case, the string collection will contain the titles of all audio items that
// match the query.
WMPLib.IWMPStringCollection2 result = (WMPLib.IWMPStringCollection2)mc.getStringCollectionByQuery("Title", q, "audio", "", false);
// Display the results by adding them to a list box.
for (int i = 0; i < result.count; i++)
{
queryResults.Items.Add(result.Item(i));
}
' Get a new Query interface.
Dim mc As WMPLib.IWMPMediaCollection2 = player.mediaCollection
Dim q As WMPLib.IWMPQuery = mc.createQuery()
' Add two conditions to the Query.
q.addCondition("WM/Composer", "Equals", "Antonio Vivaldi")
q.addCondition("Title", "Contains", "Trio")
' Query the media collection and get a string collection containing the result.
' In this case, the string collection will contain the titles of all audio items that
' match the query.
Dim result As WMPLib.IWMPStringCollection2 = mc.getStringCollectionByQuery("Title", q, "audio", "", False)
' Display the results by adding them to a list box.
For i As Integer = 0 To (result.count - 1)
queryResults.Items.Add(result.Item(i))
Next i
Requirements
| Version |
Windows Media Player 11. |
| Namespace |
WMPLib |
| Assembly |
|