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 Object
Log Parser COM API Overview
C# Example

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