php校验表单检测字段是否为空的方法

2024-05-04 23:33:01

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这篇文章主要介绍了php校验表单检测字段是否为空的方法,涉及php验证表单的技巧,非常具有实用价值,需要的朋友可以参考下

本文实例讲述了php校验表单检测字段是否为空的方法。分享给大家供大家参考。具体如下：

php校验表单，检测字段是否为空，当表单中有未填写的字段，则会显示错误信息。

<html>

<body>

<form METHOD="POST" ACTION="ErrorCheck.php">

<h1>Contact Information</h1>

<label>Nickname:</label>

<input TYPE="TEXT" NAME="nickname">

<label>Title:</label>

<input TYPE="TEXT" NAME="title">

<br />

<input TYPE="SUBMIT" VALUE="Submit">

<br />

<input TYPE="RESET" VALUE="Clear the Form">

</form>

</body>

</html>

php后端代码，保存为： ErrorCheck.php

<html>

<body>

<?php

$errorcount=0;

if (!trim($_POST['nickname'])) {

echo "<br /><b>Nickname</b> is required.";

$errorcount++;

}

if (!trim($_POST['title'])) {

echo "<br /><b>Title</b> is required.";

$errorcount++;

}

if ($errors > 0)

echo "<br /><br />Please use your browser's back button " .

"to return to the form, and correct error(s)";

?>

</body>

</html>

trim()函数可以去除字符串中的前后空字符

" " (ASCII 32 (0×20)), an ordinary space.

"/t" (ASCII 9 (0×09)), a tab.

"/n" (ASCII 10 (0x0A)), a new line (line feed).

"/r" (ASCII 13 (0x0D)), a carriage return.

"/0″ (ASCII 0 (0×00)), the NUL-byte.

"/x0B" (ASCII 11 (0x0B)), a vertical tab.