[1] The variables cannot be passed between pages. Get, post, session is automatically closed in the latest php version. Therefore, to obtain the submission from the previous page, you must use $_GET['foo'], $_POST['foo'], $_SESSION['foo'] to get
Of course, you can also modify the automatic global variable to On (change it to register_globals = On); considering compatibility, it is better to force yourself to be familiar with the new writing method.
【2】With the apache2 under Win32, it will cause an error when passing Chinese parameters using the get method.
?a=Hello&b=You are also
Passing parameters will cause an internal error
Solution: "?a=".urlencode(Hello)."&b=".urlencode(Hello too)
.............
【3】The session under win32 does not work properly
Default session.save_path=/tmp
This is obviously a configuration under Linux. PHP cannot read and write session files under win32, so the session cannot be used.
Just change it to an absolute path, for example session.save_path= c:\windows\temp
【4】Show error message
When display_errors = On and error_reporting = E_ALL, all errors and prompts will be displayed. It is best to open them during debugging to correct errors. If you use the previous php writing method, the error message is mostly about undefined variables. There will be prompts when calling variables before assignment. The solution is to detect or block.
For example, if(isset($foo)) echo $foo or echo @$foo
【5】Email() cannot be sent under Win32
Sendmail configured in Linux can be sent, and under win32, you need to call the SMTP server to send emails.
Modified SMTP = ip //IP is a SMTP server without verification function (it is difficult to find on the Internet)
The best solution to send emails to PHP is to use socket to send them directly to the other party's email server without forwarding the server.
【6】If the first installed mysql does not have a password set, it should be used
update set password="yourpassword" where user="root"
Change password
【7】header already sent
This error usually occurs when you use HEADER. It may be caused by several reasons: 1. You PRING or ECHO before using HEADER 2. You have blank lines in front of the current file 3. You may INCLUDE a file, and there are blank lines at the end of the file or output this error will also occur. !
【8】No change after the change
Restart the web server, such as IIS, Apache, etc., and then the latest settings will be applied.
【9】Php is installed on 2003 (I would like to advise on the ISAPI installation method)
PHP4 seems to have some conflicts with 2003, so it can only be installed in CGI mode.
Step 1: First, go to an installer. I installed it: php-4.2. You can also find the latest version. Before installing php-4.2., make sure that your IIS6.0 is started and accessible. After installation, on the default website --> Application Configuration
Step 2: Click on web service extension --> Create a new web service extension.
Step 3: Extension-->php, and then add
Step 4: Add the path found.
Step 5: Just confirm!
Step 6: Select the service extension of php and click Allow.
【10】
Sometimes the SQL statement does not work and the database operation fails.
The easiest debugging method, echo the sql, see if the value of the variable can be obtained.
【11】The difference between include and require
There is not much difference between the two. If the file you want to include does not exist, include prompts notice, and then continues to execute the following statement. Require prompts a fatal error and exit.
According to my test, they are included first and then executed on win32 platform, so it is best not to include or require statements in the included file, as this will cause directory confusion. Maybe the situation under *nux is different, and it has not been tested yet.
If a file does not want to be included multiple times, you can use include_once or require_once## to read and write document data.
function r($file_name) {
$filenum=@fopen($file_name,"r");
@flock($filenum,LOCK_SH);
$file_data=@fread($filenum,filesize($file_name));
@fclose($filenum);
return $file_data;
}
function w($file_name,$data,$method="w"){
$filenum=@fopen($file_name,$method);
flock($filenum,LOCK_EX);
$file_data=fwrite($filenum,$data);
fclose($filenum);
return $file_data;
}
【12】The difference between isset() and empty()
Both are used for testing variables
But isset() is to test whether the variable is assigned, while empty() is to test whether a variable that has been assigned is empty.
If a variable is not assigned, it is allowed to refer to it in PHP, but there will be notice prompts.
If a variable is assigned a null value, $foo="" or $foo=0 or $foo=false, then empty($foo) returns true, and isset($foo) also returns true, which means that the null value will not cancel a variable.
To log out a variable, you can use unset($foo) or $foo=NULL
【13】mysql query statement contains keywords
When php querying mysql, sometimes there will be keywords for mysql table or column names.
There will be errors in the query at this time. For example, the table name is order, an error will occur during query.
The simple method is to distinguish the table name or column name in the SQL statement with `[tab key].
For example select * from `order`
【14】 Methods to upload multiple files at once through the HTTP protocol
There are two ideas, two implementations of the same method. The specific program needs to be designed by yourself
1. Set multiple file input boxes in form and name their names with an array, as follows:
<form action="" method=post>
<input type=file name=usefile[]>
<input type=file name=usefile[]>
<input type=file name=usefile[]>
</form>
In this way, do the following tests on the server side
echo "<pre>";
print_r($_FILES);
echo "</pre>";
1. Set multiple file input boxes in form, but the names are different, as follows:
<form action="" method=post>
<input type=file name=usefile_a>
<input type=file name=usefile_b>
<input type=file name=usefile_c>
</form>
Do the same test on the server side:
echo "<pre>";
print_r($_FILES);
echo "</pre>";
Of course, you can also modify the automatic global variable to On (change it to register_globals = On); considering compatibility, it is better to force yourself to be familiar with the new writing method.
【2】With the apache2 under Win32, it will cause an error when passing Chinese parameters using the get method.
?a=Hello&b=You are also
Passing parameters will cause an internal error
Solution: "?a=".urlencode(Hello)."&b=".urlencode(Hello too)
.............
【3】The session under win32 does not work properly
Default session.save_path=/tmp
This is obviously a configuration under Linux. PHP cannot read and write session files under win32, so the session cannot be used.
Just change it to an absolute path, for example session.save_path= c:\windows\temp
【4】Show error message
When display_errors = On and error_reporting = E_ALL, all errors and prompts will be displayed. It is best to open them during debugging to correct errors. If you use the previous php writing method, the error message is mostly about undefined variables. There will be prompts when calling variables before assignment. The solution is to detect or block.
For example, if(isset($foo)) echo $foo or echo @$foo
【5】Email() cannot be sent under Win32
Sendmail configured in Linux can be sent, and under win32, you need to call the SMTP server to send emails.
Modified SMTP = ip //IP is a SMTP server without verification function (it is difficult to find on the Internet)
The best solution to send emails to PHP is to use socket to send them directly to the other party's email server without forwarding the server.
【6】If the first installed mysql does not have a password set, it should be used
update set password="yourpassword" where user="root"
Change password
【7】header already sent
This error usually occurs when you use HEADER. It may be caused by several reasons: 1. You PRING or ECHO before using HEADER 2. You have blank lines in front of the current file 3. You may INCLUDE a file, and there are blank lines at the end of the file or output this error will also occur. !
【8】No change after the change
Restart the web server, such as IIS, Apache, etc., and then the latest settings will be applied.
【9】Php is installed on 2003 (I would like to advise on the ISAPI installation method)
PHP4 seems to have some conflicts with 2003, so it can only be installed in CGI mode.
Step 1: First, go to an installer. I installed it: php-4.2. You can also find the latest version. Before installing php-4.2., make sure that your IIS6.0 is started and accessible. After installation, on the default website --> Application Configuration
Step 2: Click on web service extension --> Create a new web service extension.
Step 3: Extension-->php, and then add
Step 4: Add the path found.
Step 5: Just confirm!
Step 6: Select the service extension of php and click Allow.
【10】
Sometimes the SQL statement does not work and the database operation fails.
The easiest debugging method, echo the sql, see if the value of the variable can be obtained.
【11】The difference between include and require
There is not much difference between the two. If the file you want to include does not exist, include prompts notice, and then continues to execute the following statement. Require prompts a fatal error and exit.
According to my test, they are included first and then executed on win32 platform, so it is best not to include or require statements in the included file, as this will cause directory confusion. Maybe the situation under *nux is different, and it has not been tested yet.
If a file does not want to be included multiple times, you can use include_once or require_once## to read and write document data.
function r($file_name) {
$filenum=@fopen($file_name,"r");
@flock($filenum,LOCK_SH);
$file_data=@fread($filenum,filesize($file_name));
@fclose($filenum);
return $file_data;
}
function w($file_name,$data,$method="w"){
$filenum=@fopen($file_name,$method);
flock($filenum,LOCK_EX);
$file_data=fwrite($filenum,$data);
fclose($filenum);
return $file_data;
}
【12】The difference between isset() and empty()
Both are used for testing variables
But isset() is to test whether the variable is assigned, while empty() is to test whether a variable that has been assigned is empty.
If a variable is not assigned, it is allowed to refer to it in PHP, but there will be notice prompts.
If a variable is assigned a null value, $foo="" or $foo=0 or $foo=false, then empty($foo) returns true, and isset($foo) also returns true, which means that the null value will not cancel a variable.
To log out a variable, you can use unset($foo) or $foo=NULL
【13】mysql query statement contains keywords
When php querying mysql, sometimes there will be keywords for mysql table or column names.
There will be errors in the query at this time. For example, the table name is order, an error will occur during query.
The simple method is to distinguish the table name or column name in the SQL statement with `[tab key].
For example select * from `order`
【14】 Methods to upload multiple files at once through the HTTP protocol
There are two ideas, two implementations of the same method. The specific program needs to be designed by yourself
1. Set multiple file input boxes in form and name their names with an array, as follows:
<form action="" method=post>
<input type=file name=usefile[]>
<input type=file name=usefile[]>
<input type=file name=usefile[]>
</form>
In this way, do the following tests on the server side
echo "<pre>";
print_r($_FILES);
echo "</pre>";
1. Set multiple file input boxes in form, but the names are different, as follows:
<form action="" method=post>
<input type=file name=usefile_a>
<input type=file name=usefile_b>
<input type=file name=usefile_c>
</form>
Do the same test on the server side:
echo "<pre>";
print_r($_FILES);
echo "</pre>";