This chapter is from the book
This chapter is from the book
This chapter is from the book
Error Reporting
The second of the three PHP configuration issues you should be aware of is error reporting. There are eight types of errors in PHP plus three user-defined errors (which aren't covered here). Table 3.1 lists the four most important error types, along with a description and example.
You can determine what errors PHP reports on using the error_reporting() function. The function takes either a number or a constant (a nonquoted string with a predetermined meaning) to adjust the levels. For example:
error_reporting (0); // Turn off entirely. error_reporting (E_ALL); // Report → everything. error_reporting (E_ALL & ~E_NOTICE); → // Don't show notices.
The last example states that you want to see all error messages except notices (the & ~ means and not). You'll apply this setting to the handle_form.php page to get rid of those pesky error messages (Figure 3.12).
Script 3.6. You adjust PHP's level of error reporting to give you more or less feedback.
1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML
1.0 Transitional//EN"
2 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-
transitional.dtd">
3 <html xmlns="http://www.w3.org/1999/xhtml">
4 <head>
5 <meta http-equiv="content-type"
content="text/html; charset=
iso-8859-1" />
6 <title>Your Feedback</title>
7 </head>
8 <body>
9 <?php // Script 3.6 - handle_form.php
(third version after Scripts 3.4 and 3.5)
10
11 ini_set ('display_errors', 1); // Let me
learn from my mistakes.
12 error_reporting (E_ALL & ~ E_NOTICE); //
Don't show notices.
13
14 // This page receives the data from
feedback.html.
15 // It will recieve: title, name, email,
response, comments, and submit.
16
17 print "Thank you $title $name for your
comments. <br />";
18 print "You stated that you found this
example to be $response and added:
$comments";
19
20 ?>
21 </body>
22 </html>
Table 3.1. The four most common error types in PHP.
|
PHP Error Types |
||
|
TYPE |
DESCRIPTION |
EXAMPLE |
|
Notice |
Nonfatal error that may or may not be indicative of a problem |
Referring to a variable that has no value |
|
Warning |
Nonfatal error that is most likely problematic |
Passing the wrong type of parameter to a function |
|
Parse error |
Fatal error caused by a syntactical mistake |
Omission of a semicolon or an imbalance of quotation marks, braces, or parentheses |
|
Error |
A general fatal error |
Memory allocation problem |
To adjust error reporting:
- Open handle_form.php in your text editor (Script 3.5).
- After the ini_set() line, enter the following (Script 3.6):
error_reporting(E_ALL&~E_NOTICE);
- Save the file as handle_form.php.
Upload the file to your Web server and test it in your Web browser (Figures 3.13 and 3.14).
Figure 3.13 Trying the form one more time...
Figure 3.14 ...and now the notices are gone.
At this point, you should either see a successful handling of the form (Figure 3.9) or be missing the variable values but not see the error messages (Figure 3.14). The next section of this chapter will address the missing variable values.
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