Why Doesn't PHP Properly Handle `enctype=text/plain` in `method=post` Forms?

Form Data Transmission with "enctype=text/plain" in "method=post" Requests

The issue pertains to the usage of "enctype=text/plain" within a form's "method=post" attribute. While this encoding is compatible with the "method=get" attribute, it raises compatibility issues when paired with "method=post".

Explanation

PHP does not inherently handle "text/plain" encoding when processing "post" requests. As such, the form data is not correctly populated into the $_POST array. Instead, the data is stored in the $HTTP_RAW_POST_DATA variable.

Distinction Between GET and POST Encoding

In "enctype=text/plain" "method=get" scenarios, the variables are URL-encoded and included in the query string. This process conveniently handles character encoding without ambiguity.

However, in "enctype=text/plain" "method=post" scenarios, the variables are sent in the POSTDATA header. This approach lacks inherent URL-encoding, leading to potential data ambiguity.

Valid Encodings for "method=post" Requests

PHP only recognizes two valid encodings for "method=post" requests:

• application/x-www-form-urlencoded
• multipart/form-data

The former encoding is the default, while the latter is required for file uploads.

Consequences of Using "text/plain" Encoding

Utilizing "text/plain" encoding with "method=post" can result in data corruption. For instance, if multiple variables with similar names exist, the data may become indistinguishable, leading to incorrect processing on the server-side.

Alternative to "text/plain" Encoding

If encoding characters is desired, consider using the "application/x-www-form-urlencoded" encoding instead. This approach URL-encodes the form data to ensure correct transmission and eliminates the need for additional character management.

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