isNull Method
Returns a Boolean value indicating if an output record field is NULL.
Script Syntax
value = objRecord.isNull( index );
value = objRecord.isNull( fieldName );
Parameters
- index
- An integer containing the 0-based index of the field in the query output records. The index must be less than the number of fields returned by the getColumnCount method of the LogRecordSet object.
- fieldName
- A string containing the name of the field in the query output records.
Return Value
A Boolean value indicating if the specified output record field is NULL.
Examples
JScript example:
var oLogQuery = new ActiveXObject("MSUtil.LogQuery"); // Create query text var strQuery = "SELECT TimeGenerated, SourceName, EventID, Message, Data FROM System"; // Execute query and receive a LogRecordSet var oRecordSet = oLogQuery.Execute( strQuery ); // Visit all records while( !oRecordSet.atEnd() ) { // Get a record var oRecord = oRecordSet.getRecord(); // Display record information WScript.Echo( "TimeGenerated: " + oRecord.getValue("TimeGenerated") ); WScript.Echo( "SourceName : " + oRecord.getValue(1) ); WScript.Echo( "EventID : " + oRecord.getValue(2) ); if( !oRecord.isNull(3) ) { WScript.Echo( "Message : " + oRecord.getValue(3) ); } else { WScript.Echo( "Message : <null>" ); } if( !oRecord.isNull("Data") ) { WScript.Echo( "Data : " + oRecord.getValue(4) ); } else { WScript.Echo( "Data : <null>" ); } // Advance LogRecordSet to next record oRecordSet.moveNext(); } // Close LogRecordSet oRecordSet.close();VBScript example:
Dim oLogQuery Dim oRecordSet Dim strQuery Dim f Dim val Set oLogQuery = CreateObject("MSUtil.LogQuery") ' Create query text strQuery = "SELECT TimeGenerated, SourceName, EventID, Message, Data FROM System" ' Execute query and receive a LogRecordSet Set oRecordSet = oLogQuery.Execute( strQuery ) ' Visit all records DO WHILE NOT oRecordSet.atEnd ' Get a record Set oRecord = oRecordSet.getRecord ' Display record information WScript.Echo "TimeGenerated: " & oRecord.getValue("TimeGenerated") WScript.Echo "SourceName : " & oRecord.getValue(1) WScript.Echo "EventID : " & oRecord.getValue(2) If oRecord.isNull(3) = False Then WScript.Echo "Message : " & oRecord.getValue(3) Else WScript.Echo "Message : <null>" End If If oRecord.isNull("Data") = False Then WScript.Echo "Data : " & oRecord.getValue(4) Else WScript.Echo "Data : <null>" End If ' Advance LogRecordSet to next record oRecordSet.moveNext LOOP ' Close RecordSet oRecordSet.close
See also:
LogRecord ObjectLog Parser COM API Overview
C# Example