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loopsjstlhttp-request-parameters

Iterate over param JSTL using foreach

I have list of request parameters that the key is an integer, like 

0=hello&1=by&2=sss .......

I want to iterate over this list of parameters using foreach:

<c:forEach var="i" begin="0" end="${fn:length(param)-1}" >
  <c:out value="${param['i']}"/>
</c:forEach>
Solution

  • OK, see if this trick works:

    <c:forEach var="i" begin="0" end="${fn:length(param)-1}" >
    <c:set var="iString" value="t${i}"/>
    <c:out value="${param[fn:substringAfter(1, iString, fn:length(iString))]}"/>
</c:forEach>

    1) The c:set statement converts i from a number to a string of the form "t0, t1, t2 .."

    2) Now strip off the first character, and substringAfter returns a string containing just the number.

    It's super close. I believe all you need to do is remove the apostrophes:

    From:

    ${param['i']}

    To:

    ${param[i]}

    With the apostrophes you are looking for a parameter named "i" instead of a parameter named "0".