1<?xml version="1.0" encoding="UTF-8"?> 2<helpdocument version="1.0"> 3 4<!--*********************************************************** 5 * 6 * Licensed to the Apache Software Foundation (ASF) under one 7 * or more contributor license agreements. See the NOTICE file 8 * distributed with this work for additional information 9 * regarding copyright ownership. The ASF licenses this file 10 * to you under the Apache License, Version 2.0 (the 11 * "License"); you may not use this file except in compliance 12 * with the License. You may obtain a copy of the License at 13 * 14 * http://www.apache.org/licenses/LICENSE-2.0 15 * 16 * Unless required by applicable law or agreed to in writing, 17 * software distributed under the License is distributed on an 18 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 19 * KIND, either express or implied. See the License for the 20 * specific language governing permissions and limitations 21 * under the License. 22 * 23 ***********************************************************--> 24 25 26 27 28<meta> 29<topic id="textsbasicshared03102600xml" indexer="include"> 30<title id="tit" xml-lang="en-US">IsNull Function [Runtime]</title> 31<filename>/text/sbasic/shared/03102600.xhp</filename> 32</topic> 33</meta> 34<body> 35<section id="isnull"> 36<bookmark xml-lang="en-US" branch="index" id="bm_id3155555"><bookmark_value>IsNull function</bookmark_value> 37<bookmark_value>Null value</bookmark_value> 38</bookmark> 39<paragraph role="heading" id="hd_id3155555" xml-lang="en-US" level="1" l10n="U" oldref="1"><link href="text/sbasic/shared/03102600.xhp" name="IsNull Function [Runtime]">IsNull Function [Runtime]</link></paragraph> 40<paragraph role="paragraph" id="par_id3146957" xml-lang="en-US" l10n="U" oldref="2">Tests if a Variant contains the special Null value, indicating that the variable does not contain data.</paragraph> 41</section> 42<paragraph role="heading" id="hd_id3150670" xml-lang="en-US" level="2" l10n="U" oldref="3">Syntax:</paragraph> 43<paragraph role="paragraph" id="par_id3150984" xml-lang="en-US" l10n="U" oldref="4">IsNull (Var)</paragraph> 44<paragraph role="heading" id="hd_id3149514" xml-lang="en-US" level="2" l10n="U" oldref="5">Return value:</paragraph> 45<paragraph role="paragraph" id="par_id3145609" xml-lang="en-US" l10n="U" oldref="6">Bool</paragraph> 46<paragraph role="heading" id="hd_id3149669" xml-lang="en-US" level="2" l10n="U" oldref="7">Parameters:</paragraph> 47<paragraph role="paragraph" id="par_id3159414" xml-lang="en-US" l10n="U" oldref="8"> 48<emph>Var:</emph> Any variable that you want to test. This function returns True if the Variant contains the Null value, or False if the Variant does not contain the Null value.</paragraph> 49<paragraph role="paragraph" id="par_idN1062A" xml-lang="en-US" l10n="NEW"> 50<emph>Null</emph> - This value is used for a variant data sub type without valid contents.</paragraph> 51<embed href="text/sbasic/shared/00000003.xhp#errorcode"/> 52<embed href="text/sbasic/shared/00000003.xhp#err5"/> 53<paragraph role="heading" id="hd_id3153381" xml-lang="en-US" level="2" l10n="U" oldref="9">Example:</paragraph> 54<paragraph role="paragraph" id="par_id3154140" xml-lang="en-US" l10n="U" oldref="10">Sub ExampleIsNull</paragraph> 55<paragraph role="paragraph" id="par_id3145172" xml-lang="en-US" l10n="U" oldref="11">Dim vVar As Variant</paragraph> 56<paragraph role="paragraph" id="par_id3144760" xml-lang="en-US" l10n="U" oldref="12">msgbox IsNull(vVar)</paragraph> 57<paragraph role="paragraph" id="par_id3153970" xml-lang="en-US" l10n="U" oldref="13">end sub</paragraph> 58</body> 59</helpdocument> 60