這篇文章主要介紹了php校驗表單檢測字段是否為空的方法,涉及php驗證表單的技巧,非常具有實用價值,需要的朋友可以參考下
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。
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 <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
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 <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
? 1 2 3 4 5 6 " " (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. " ″ (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。
