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How to check whether a field is empty in php verification form, verify field_PHP tutorial

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Jul 13, 2016 am 10:01 AM

phpcheckform

php校验表单检测字段是否为空的方法，校验字段

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 id="Contact-Information">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>
<&#63;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)";
 &#63;>
</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.

希望本文所述对大家的php程序设计有所帮助。

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