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How can I pre-populate a HTML radio button using JSP, depending on the value in the database?

BalusC
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Gary Deuces Rozanski
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2 Answers2

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You just need to let JSP print the checked attribute of the HTML <input type="radio"> element. Easiest way to do that is using the conditional operator ?: in EL. Here's a kickoff example:

<input type="radio" name="foo" value="one" ${bean.foo == 'one' ? 'checked' : ''}/>
<input type="radio" name="foo" value="two" ${bean.foo == 'two' ? 'checked' : ''}/>
...

Or if you have all available input values in some collection like List<String>, then do:

<c:forEach items="${foos}" var="foo">
  <input type="radio" name="foo" value="${foo}" ${bean.foo == foo ? 'checked' : ''}/>
</c:forEach>

Either way, it should ultimately end up as follows in the generated HTML if ${bean.foo} equals to "two":

<input type="radio" name="foo" value="one" />
<input type="radio" name="foo" value="two" checked />
...

See also:

BalusC
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  • Excellent, thanks again BalusC - I will take this away and use these examples! Appreciate your help. – Gary Deuces Rozanski Nov 15 '11 at 18:05
  • Hey BalusC, in the second example you provided could you just give me a heads up on what the difference is between ${foos} and ${foo} I don't think I understand beans & foos enough to be able to follow your examples. – Gary Deuces Rozanski Nov 15 '11 at 19:50
  • The `${foos}` is the collection. The `${foo}` is the currently iterated item. See also http://stackoverflow.com/questions/1727603/places-where-java-beans-used, http://stackoverflow.com/questions/3177733/how-to-avoid-java-code-in-jsp-files and http://stackoverflow.com/tags/servlets/info – BalusC Nov 15 '11 at 19:52
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Pure JSP Scriplets

<input type="radio" name="gender" value="male" <% if (resultSet.getString("gender").equals("male")) out.print("checked"); else out.print(""); %> />
<input type="radio" name="gender" value="female" <% if (resultSet.getString("gender").equals("female")) out.print("checked"); else out.print(""); %> />
antelove
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