Various methods to change the SELECT option of HTML drop-down box_HTML/Xhtml

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Various methods to change the SELECT option of HTML drop-down box_HTML/Xhtml_Web page production

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May 16, 2016 pm 04:40 PM

selectdrop down boxOptions

The HTML page returned after submitting the form is re-rendered. Neither the value nor selectedIndex attributes of the SELECT control can make the drop-down box retain the state before submitting the form.

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The code is as follows:

A temporary solution is to add a script at the end of the vm file to assign a value to the drop-down box :

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The code is as follows:

Another solution is to set the default selected item :

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The code is as follows:

The way to write it in VTL is :

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code As follows:

For velocity, comparisons, especially those involving inequality comparisons (greater than or less than) are relatively difficult to implement. Now I want to display the file sizes on the page in categories (Bytes, MB, GB), so it involves comparing filesize sizes. Is there a better way to achieve this?
For example, the following code:

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The code is as follows: # if ($filesize > 1024 && $filesize #set($ksize = $filesize 24)

File Size: $ksize KB

#elseif ($filesize > 1048567 && $filesize #set($msize=$filesize 48567)

File Size: $msize MB
#elseif ($filesize > 1073731824)
#($gsize=$filesize 73731824)

File Size: $gsize GB
#else

File Size: $filesize Bytes
#end

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The code is as follows:

<SPAN style="FONT-FAMILY: Arial, Helvetica, sans-serif"&gt ;<SPAN style="WHITE-SPACE: normal"> </div></SPAN></SPAN>

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