Six ways to handle escape characters in php

PHP escape character processing:

In PHP development, in order to avoid program exceptions caused by special characters in string data, characters need to be escaped. At this time, you need to use the escape characters in PHP.

The escape character is a backslash (\) followed by a special character, which means escaping the character. PHP supports a variety of escape characters, including the following:

1. \n: Line feed character
2. \r: Carriage return character
3. \t: System Symbol
4. \': single quotation mark
5. \": double quotation mark
6. \: backslash symbol (because backslash itself is also an escape character, so it is needed Use two backslashes to represent a backslash symbol)

The following is a simple example code that shows how to use escape characters to handle strings.

$raw_str = "It's a \"test\" string.\n";
$escaped_str = addslashes($raw_str);
echo $escaped_str;

The above code The double quotes and newline characters in the string variable $raw_str are escaped, and the resulting $escaped_str string can be safely transmitted, stored or otherwise operated. The output result is as follows:

It\'s a \"test\" string.\n

In actual During development, there are other application scenarios for escape characters. For example, when inserting a string into a SQL statement, special characters in the string also need to be escaped to avoid SQL injection attacks. In this case, the following code should be used :

$raw_str = "It's a \"test\" string.";
$escaped_str = mysqli_real_escape_string($connection, $raw_str);
$sql = "INSERT INTO test_table (test_column) VALUES ('$escaped_str')";
mysqli_query($connection, $sql);

The above code uses the mysqli_real_escape_string() function to safely escape the string and insert the escaped string into the SQL statement. This can avoid SQL injection attacks.

In general, escape characters are widely used in PHP development. Programmers should be proficient in the usage of various escape characters to ensure that the program is safe and reliable.

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