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How to implement the query when the php text box is empty

angryTom
angryTomOriginal
2019-11-05 14:36:503047browse

How to implement the query when the php text box is empty

php does not query if the text box is empty

phpIt is very simple to determine whether a variable is empty, just use empty That’s it. The following demonstrates how to make the form content empty without querying.

1. First write the query form

Submit a wd to the server through get

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<form action="a.php" method="get">
<input type="search" name="wd">
<input type="submit" value="查询">
</form>
</body>
</html>

2. Then make a judgment. The wd is the content of the text box. Use empty for empty judgment

<?php
if(!isset($_GET[&#39;wd&#39;])) {
exit;
}
if (empty($_GET[&#39;wd&#39;])) {
die(&#39;为空&#39;);
}
// 在这进行查询处理
echo &#39;正在查询&#39;, $_GET[&#39;wd&#39;], &#39;...&#39;;
?>

When the content of the text box is empty, the program will execute die and exit, and subsequent query statements will not be executed.

Effect:

How to implement the query when the php text box is empty

How to implement the query when the php text box is empty

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