Multiple ways to change the SELECT options in an HTML drop-down box

After the form is submitted, the returned HTML page is re-rendered, and neither the value nor the selectedIndex attribute of the SELECT control can make the drop-down box retain the state before the form is submitted.

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The code is as follows:

<SELECT id="idState" style="width:150" name="state" selectedIndex="$!{state}">
<OPTION value="">All</OPTION>
<OPTION value="1">Pass</OPTION>
<OPTION value="2">Not passed</OPTION>
<OPTION value="3">Pending</OPTION>
</SELECT>

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 a default selection :

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The code is as follows:

<SELECT id="idState" style="width:150" name="state" value="$!{state}">
<OPTION value="">All</OPTION>
<OPTION value="1">Pass</OPTION>
<OPTION value="2" SELECTED>Not passed</OPTION>
<OPTION value="3">Pending</OPTION>
</SELECT>

The VTL way of writing is :

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The code is as follows:

<SELECT id="idState" style="width:150" name="state" value="$!{state}">
<OPTION value="">All</OPTION>
<OPTION #if($!{state} == 1) SELECTED #end value="1">Pass</OPTION>
<OPTION #if($!{state} == 2) SELECTED #end value="2">Not passed</OPTION>
<OPTION #if($!{state} == 3) SELECTED #end value="3">To be processed</OPTION>
</SELECT>

It should be noted here that when performing == comparison, Velocity distinguishes between types. If you compare with the strings "1", "2", and "3", you will always get false.
Comparison issues in velocity <br />For velocity, comparisons, especially those involving inequality comparisons (greater than or less than), are difficult to implement. Now I want to display the file size on the page in categories (Bytes, MB, GB), which involves the problem of 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 && $filesize < 1048567)
#set($ksize = $filesize%1024)
<div class="mlt">File Size: $ksize KB
#elseif ($filesize > 1048567 && $filesize < 1073731824)
#set($msize=$filesize%1048567)
<div class="mlt">File Size: $msize MB
#elseif ($filesize > 1073731824)
#($gsize=$filesize%1073731824)
<div class="mlt">File Size: $gsize GB
#else
<div class="mlt">File Size: $filesize Bytes
#end

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The code is as follows:

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Multiple ways to change the SELECT options in an HTML drop-down box

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