{"id":192,"date":"2008-05-03T01:54:38","date_gmt":"2008-05-02T17:54:38","guid":{"rendered":"http:\/\/learn-house.idv.tw\/?p=192"},"modified":"2010-01-16T04:39:06","modified_gmt":"2010-01-15T20:39:06","slug":"phpisset%e8%88%87empty%e7%9a%84%e5%8d%80%e5%88%a5","status":"publish","type":"post","link":"https:\/\/learn-house.idv.tw\/?p=192","title":{"rendered":"[PHP]]isset()\u8207empty()\u7684\u5340\u5225"},"content":{"rendered":"

\u8cc7\u6599\u4f86\u6e90\uff1a\u601d\u60f3\u4e4b\u5730<\/a><\/p>\n

  1<\/span><?<\/span><\/span><\/span>php error_reporting(E_ALL);
<\/span>  2<\/span><\/span>echo<\/span> <\/span>‘<\/span><B>\u672a\u5b9a\u7fa9$var<\/b><Br><\/span>‘<\/span><\/span><\/span>;
<\/span>  3<\/span><\/span>echo<\/span> <\/span>"<\/span>isset\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span>  4<\/span><\/span>if<\/span> (<\/span>isset<\/span>(<\/span>$var<\/span><\/span><\/span>))
<\/span>  5<\/span><\/span><\/span>{
<\/span>  6<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span> ;
<\/span>  7<\/span><\/span><\/span>}
<\/span>  8<\/span><\/span><\/span>
<\/span>  9<\/span><\/span><\/span>
<\/span> <\/span><\/span><\/span><\/p>\n

 10<\/span><\/span>echo<\/span> <\/span>"<\/span>empty\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 11<\/span><\/span>if<\/span> (<\/span>empty<\/span>(<\/span>$var<\/span><\/span><\/span>)){
<\/span> 12<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 13<\/span><\/span><\/span>}
<\/span> 14<\/span><\/span>else<\/span><\/span><\/span>
<\/span> 15<\/span><\/span>{
<\/span> 16<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 17<\/span><\/span><\/span>}
<\/span> 18<\/span><\/span><\/span>
<\/span> 19<\/span><\/span>echo<\/span> <\/span>"<\/span>\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 20<\/span><\/span>if<\/span> (<\/span>$var<\/span><\/span><\/span>){
<\/span> 21<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 22<\/span><\/span><\/span>}
<\/span> 23<\/span><\/span>else<\/span><\/span><\/span>{
<\/span> 24<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u4e0d\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 25<\/span><\/span><\/span>}
<\/span> 26<\/span><\/span><\/span>
<\/span> 27<\/span><\/span>echo<\/span> <\/span>‘<\/span>———————————-<br><\/span>‘<\/span><\/span><\/span>;
<\/span> 28<\/span><\/span>echo<\/span> <\/span>‘<\/span><B>$var = \\<\/span>‘<\/span>\\<\/span>‘<\/span><\/b><Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 29<\/span><\/span>echo<\/span> <\/span>"<\/span>isset\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 30<\/span><\/span>$var<\/span> <\/span>=<\/span> <\/span>”<\/span><\/span><\/span>;
<\/span> 31<\/span><\/span>if<\/span> (<\/span>isset<\/span>(<\/span>$var<\/span><\/span><\/span>))
<\/span> 32<\/span><\/span><\/span>{
<\/span> 33<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span> ;
<\/span> 34<\/span><\/span><\/span>}
<\/span> 35<\/span><\/span><\/span>
<\/span> 36<\/span><\/span><\/span>
<\/span> 37<\/span><\/span>echo<\/span> <\/span>"<\/span>empty\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 38<\/span><\/span>if<\/span> (<\/span>empty<\/span>(<\/span>$var<\/span><\/span><\/span>)){
<\/span> 39<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 40<\/span><\/span><\/span>}
<\/span> 41<\/span><\/span>else<\/span><\/span><\/span>
<\/span> 42<\/span><\/span>{
<\/span> 43<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 44<\/span><\/span><\/span>}
<\/span> 45<\/span><\/span><\/span>
<\/span> 46<\/span><\/span>echo<\/span> <\/span>"<\/span>\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 47<\/span><\/span>if<\/span> (<\/span>$var<\/span><\/span><\/span>){
<\/span> 48<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 49<\/span><\/span><\/span>}
<\/span> 50<\/span><\/span>else<\/span><\/span><\/span>{
<\/span> 51<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u4e0d\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 52<\/span><\/span><\/span>}
<\/span> 53<\/span><\/span>echo<\/span> <\/span>‘<\/span>———————————-<br><\/span>‘<\/span><\/span><\/span>;
<\/span> 54<\/span><\/span>echo<\/span> <\/span>‘<\/span><B>$var = 0<\/b><Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 55<\/span><\/span>echo<\/span> <\/span>‘<\/span>isset\u6e2c\u8a66:<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 56<\/span><\/span>$var<\/span> <\/span>=<\/span> <\/span>0<\/span><\/span><\/span>;
<\/span> 57<\/span><\/span>if<\/span> (<\/span>isset<\/span>(<\/span>$var<\/span><\/span><\/span>))
<\/span> 58<\/span><\/span><\/span>{
<\/span> 59<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span> ;
<\/span> 60<\/span><\/span><\/span>}
<\/span> 61<\/span><\/span><\/span>
<\/span> 62<\/span><\/span><\/span>
<\/span> 63<\/span><\/span>echo<\/span> <\/span>"<\/span>empty\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 64<\/span><\/span>if<\/span> (<\/span>empty<\/span>(<\/span>$var<\/span><\/span><\/span>)){
<\/span> 65<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 66<\/span><\/span><\/span>}
<\/span> 67<\/span><\/span>else<\/span><\/span><\/span>
<\/span> 68<\/span><\/span>{
<\/span> 69<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 70<\/span><\/span><\/span>}
<\/span> 71<\/span><\/span><\/span>
<\/span> 72<\/span><\/span>echo<\/span> <\/span>"<\/span>\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 73<\/span><\/span>if<\/span> (<\/span>$var<\/span><\/span><\/span>){
<\/span> 74<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 75<\/span><\/span><\/span>}
<\/span> 76<\/span><\/span>else<\/span><\/span><\/span>{
<\/span> 77<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u4e0d\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 78<\/span><\/span><\/span>}
<\/span> 79<\/span><\/span>echo<\/span> <\/span>‘<\/span>———————————-<br><\/span>‘<\/span><\/span><\/span>;
<\/span> 80<\/span><\/span><\/span>
<\/span> 81<\/span><\/span>echo<\/span> <\/span>‘<\/span><B>$var = null<\/b><Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 82<\/span><\/span>echo<\/span> <\/span>‘<\/span>isset\u6e2c\u8a66:<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 83<\/span><\/span>$var<\/span> <\/span>=<\/span> <\/span>null<\/span><\/span><\/span>;
<\/span> 84<\/span><\/span>if<\/span> (<\/span>isset<\/span>(<\/span>$var<\/span><\/span><\/span>))
<\/span> 85<\/span><\/span><\/span>{
<\/span> 86<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span> ;
<\/span> 87<\/span><\/span><\/span>}
<\/span> 88<\/span><\/span><\/span>
<\/span> 89<\/span><\/span><\/span>
<\/span> 90<\/span><\/span>echo<\/span> <\/span>"<\/span>empty\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span> 91<\/span><\/span>if<\/span> (<\/span>empty<\/span>(<\/span>$var<\/span><\/span><\/span>)){
<\/span> 92<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 93<\/span><\/span><\/span>}
<\/span> 94<\/span><\/span>else<\/span><\/span><\/span>
<\/span> 95<\/span><\/span>{
<\/span> 96<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span> 97<\/span><\/span><\/span>}
<\/span> 98<\/span><\/span><\/span>
<\/span> 99<\/span><\/span>echo<\/span> <\/span>"<\/span>\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span>100<\/span><\/span>if<\/span> (<\/span>$var<\/span><\/span><\/span>){
<\/span>101<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>102<\/span><\/span><\/span>}
<\/span>103<\/span><\/span>else<\/span><\/span><\/span>{
<\/span>104<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u4e0d\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>105<\/span><\/span><\/span>}
<\/span>106<\/span><\/span>echo<\/span> <\/span>‘<\/span>———————————-<br><\/span>‘<\/span><\/span><\/span>;
<\/span>107<\/span><\/span><\/span>
<\/span>108<\/span><\/span><\/span>
<\/span>109<\/span><\/span>echo<\/span> <\/span>‘<\/span><B>$var = "php"<\/b><Br><\/span>‘<\/span><\/span><\/span>;
<\/span>110<\/span><\/span>echo<\/span> <\/span>‘<\/span>isset\u6e2c\u8a66:<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>111<\/span><\/span>$var<\/span> <\/span>=<\/span> <\/span>"<\/span>php<\/span>"<\/span><\/span><\/span>;
<\/span>112<\/span><\/span>if<\/span> (<\/span>isset<\/span>(<\/span>$var<\/span><\/span><\/span>))
<\/span>113<\/span><\/span><\/span>{
<\/span>114<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span> ;
<\/span>115<\/span><\/span><\/span>}
<\/span>116<\/span><\/span><\/span>
<\/span>117<\/span><\/span><\/span>
<\/span>118<\/span><\/span>echo<\/span> <\/span>"<\/span>empty\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span>119<\/span><\/span>if<\/span> (<\/span>empty<\/span>(<\/span>$var<\/span><\/span><\/span>)){
<\/span>120<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>121<\/span><\/span><\/span>}
<\/span>122<\/span><\/span>else<\/span><\/span><\/span>
<\/span>123<\/span><\/span>{
<\/span>124<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>125<\/span><\/span><\/span>}
<\/span>126<\/span><\/span><\/span>
<\/span>127<\/span><\/span>echo<\/span> <\/span>"<\/span>\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:<Br><\/span>"<\/span><\/span><\/span>;
<\/span>128<\/span><\/span>if<\/span> (<\/span>$var<\/span><\/span><\/span>){
<\/span>129<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>130<\/span><\/span><\/span>}
<\/span>131<\/span><\/span>else<\/span><\/span><\/span>{
<\/span>132<\/span>    <\/span>echo<\/span> <\/span>‘<\/span>\u8b8a\u91cf$var\u4e0d\u5b58\u5728!<Br><\/span>‘<\/span><\/span><\/span>;
<\/span>133<\/span><\/span><\/span>}
<\/span>134<\/span><\/span>echo<\/span> <\/span>‘<\/span>———————————-<br><\/span>‘<\/span><\/span><\/span>;
<\/span>135<\/span><\/span><\/span>
<\/span>136<\/span><\/span>?><\/span><\/span><\/span>
<\/span>137<\/span><\/span><\/span><\/span>
\u8f38\u51fa:
<\/span>\u672a\u5b9a\u7fa9$var
<\/strong>isset\u6e2c\u8a66:
empty\u6e2c\u8a66:
\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a
\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:
\u8b8a\u91cf$var\u4e0d\u5b58\u5728!
———————————-
$var = ”<\/strong>
isset\u6e2c\u8a66:
\u8b8a\u91cf$var\u5b58\u5728!
empty\u6e2c\u8a66:
\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a
\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:
\u8b8a\u91cf$var\u4e0d\u5b58\u5728!
———————————-
$var = 0<\/strong>
isset\u6e2c\u8a66:
\u8b8a\u91cf$var\u5b58\u5728!
empty\u6e2c\u8a66:
\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a
\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:
\u8b8a\u91cf$var\u4e0d\u5b58\u5728!
———————————-
$var = null<\/strong>
isset\u6e2c\u8a66:
empty\u6e2c\u8a66:
\u8b8a\u91cf$var\u7684\u503c\u70ba\u7a7a
\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:
\u8b8a\u91cf$var\u4e0d\u5b58\u5728!
———————————-
$var = "php"<\/strong>
isset\u6e2c\u8a66:
\u8b8a\u91cf$var\u5b58\u5728!
empty\u6e2c\u8a66:
\u8b8a\u91cf$var\u7684\u503c\u4e0d\u70ba\u7a7a
\u8b8a\u91cf\u76f4\u63a5\u6e2c\u8a66:
\u8b8a\u91cf$var\u5b58\u5728!
———————————-
\u8acb\u6ce8\u610f20\u884c\u6703\u89f8\u767c\u4e00\u500bNotice:<\/strong><\/span><\/span>Undefined variable: var ;\u56e0\u70ba\u4f7f\u7528\u4e00\u500b\u672a\u521d\u59cb\u5316\u7684\u8b8a\u91cf\u4e0d\u898f\u7bc4.<\/span><\/span><\/span> <\/p>\n","protected":false},"excerpt":{"rendered":"

\u8cc7\u6599\u4f86\u6e90\uff1a\u601d\u60f3\u4e4b\u5730   1<?php error_reporting(E_ALL);&nbsp…<\/span><\/p>\n

Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-192","post","type-post","status-publish","format-standard","hentry","category-5"],"_links":{"self":[{"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=\/wp\/v2\/posts\/192","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=192"}],"version-history":[{"count":0,"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=\/wp\/v2\/posts\/192\/revisions"}],"wp:attachment":[{"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=192"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=192"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/learn-house.idv.tw\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=192"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}