[Html] button problems, button Problems

[Html] button problems, button Problems
Problem:

When the type attribute is not set, the button does not work in different browsers. For example:

Html:

<! Doctype html> 
Result. php:
<?php echo $_POST['txt'] ?>
We found that the form can be submitted normally if you click ie8 or later, but under ie6 or ie7, the button does not respond.
Cause:
Why is there a difference? Because the type attribute is not set for the button, the type of the button to be parsed in different browsers is different.
Through w3school, we can find that we always need to specify the type attribute for the button. The default type of Internet Explorer (ie6 and ie7 tested) is "button", while the default value of other browsers (including W3C specifications) is "submit ". Click here for details.
Finally, let's modify the demo:
<! Doctype html> 
PS:
This article aims to remind you to specify the corresponding type for the tag when using the button.