本文實例講述了php校驗表單檢測字段是否為空的方法。分享給大家供大家參考。具體如下：
php校驗表單，檢測字段是否為空，當表單中有未填寫的字段，則會顯示錯誤信息。
<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後端代碼，保存為： 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()函數可以去除字符串中的前後空字符
" " (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.
希望本文所述對大家的php程序設計有所幫助。
