网站提供错误通知：以下代码中的未定义索引[重复]

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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP 28 answers

I am getting following error

Notice: Undefined index: criteriaparam_ex in /hermes/waloraweb018/b1876/as.vapwbcom/brindle.in/wbcom-ads-split-test/wp-content/plugins/wbcom-ads-split-test-master/wb-ad-sense.php on line 687

in following code lines

elseif( isset( $segment['criteriaparam_ex'] ) || ($segment['criteriaparam_ex']!="" ) && is_single( explode( ',', $segment['criteriaparam_ex'] ) ) )

Thanks

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Condition should be:

elseif( isset( $segment['criteriaparam_ex'] ) && $segment['criteriaparam_ex'] !=""  && is_single( explode( ',', $segment['criteriaparam_ex'] ) ) )