Role of enctype = multipart/form-data in form on the webpage

Enctype = "multipart/form-Data" is used to upload images in a form.

ArticleSource: http://hi.baidu.com/greengain/blog/item/e9c02855f564e6c0b645ae17.html

<Form name = "userinfo" method = "Post" Action = "first_submit.php" enctype = "multipart/form-Data">
Enctype = "multipart/form-Data" is set in the form label to ensure that the uploaded files are properly encoded.
As follows:
<Tr>
<TD Height = "30" altd = "right"> upload the Business License Image: </TD>
<TD> <input type = "file" name = "uploadfile" size = "34" onchange = "checkimage ()"> </TD>
</Tr>
Add enctype = "multipart/form-data ".

Enctype = "multipart/form-Data" in the form,Is to set the form mime encoding. By default, the encoding format is application/X-WWW-form-urlencoded and cannot be used for file upload. Only multipart/form-data can be used to completely transmit file data, perform the following operations.
Enctype = "multipart/form-Data" is used to upload binary data. The input value in form is passed in binary format.
The input value in form is passed in binary format, so the request will not get the value. That is to say, this section is addedCode, The request will fail to be passed. When the form value is added to the database, the following is used:

Smartupload su = new smartupload (); // create a new smartupload object

Su. getrequest (). getparametervalues (); returns the array value.

Su. getrequest (). getparameter (); obtain a single parameter value