选中复选框时如何使字段为必填项

Question

hello i am new to jsp and javascript, and i would like to a make a field required when the checkbox is checked,

            <tr>
            <th class="clsTableHeaderLeft">InterCompany</th>
            <td class="clsDisplayText"> 
<%              if (!tHideField.equals("")){
                    out.println(tRecord.get(idxInterComFlag).toString());
                }

%>          
                <input type="checkbox" class="clsInputText" <%=tHideField%> name="txtInterComFlag"  onchange="chgStatus(txtStatus);" size="25" maxlength="20" 

                <%=tRecord.get(idxInterComFlag).toString().equals("Y")?" checked":""%>
                />

            </td>
        </tr> 

        <tr>
            <th class="clsTableHeaderLeft">Entity Code</th>
            <td class="clsDisplayText">
<%              if (!tHideField.equals("")){
                    out.println(tRecord.get(idxInterComCode).toString());
                }

%>          


                <input type="text" class="clsInputText" <%=tHideField%> name="txtInterComCode"  size="25" maxlength="20" />


            </td>
        </tr>

also the checkbox value is 'on' when checked , how can I make it to Y or N? thank you!

Answer 1

I had a same requirement, so i Choose to follow this flow:

• Create an onclick function at check box
• Get element ID of the html input element that needs to be changed
• create new html input element as required and replace it using Java script.

Here is my sample Code:

 function fxctco() { var newHTML="<input type='number' name='fctc' required/>"; document.getElementById("ctc").innerHTML = newHTML; } 

 <table><tr><TD ><input type="radio" name="fx"value="YES" onClick="fxctco()"> Yes <input type="radio" name="fx"value="NO" checked> No</TD></tr> <tr><TD id="ctc"> <INPUT TYPE="number" NAME="fctc" /></TD></tr> <tr> <TD align="center"><INPUT TYPE="submit" class="button" VALUE="submit"></TD> </tr> </table>