In PHP,htmlentities()andhtmlspecialchars()Both are used to prevent XSS (Cross Site scripting attacks), with the main purpose of converting characters with special meanings in HTML into entities to avoid being parsed by browsers into real HTML tags. But theirDifferent conversion rangesThe specific differences are as follows:

✅ 1. htmlspecialchars()- Convert some special characters

✅ It will convert the following 5 characters:

When outputting content containing partial HTML, such as comments, forms, user input - avoid user input < script>When parsed as a script.

Example code:

echo htmlspecials( "  < b> Hello<  /b>  ");
// 输出：<b>Hello</b>

✅ 2. htmlentities()- Convert all characters with HTML entities

✅ It will convertAll characters represented by HTML entitiesNot limited to the five mentioned above.

For example:

✅ Purpose:

When you want the page to displayPlain text rather than any HTML or special symbolsFor example, user uploaded content is displayed directly on the webpage without allowing any HTML tags or special characters.

Example code:

echo htmlentities("<b>Hello & Welcome ©</b>");
// 输出：<b>Hello & Welcome ©</b>

🆚 Summary of Differences Comparison Table:

🔄 Common parameter supplements (both functions support):

htmlspecials($string, ENT_QUOTES, " UTF-8");
htmlentities($string, ENT_QUOTES, " UTF-8");

• ENT_QUOTESSimultaneously convert single quotation marks'And double quotation marks"

• " UTF-8"Ensure to use UTF-8 encoding to avoid garbled characters

✅ Conclusion recommendation:

If you are unsure which one to use in an actual project, you can judge based on the principle of "whether to allow HTML tags to exist". If there are specific usage scenarios, I can help you choose a more suitable method in detail.