Set variable in relation to a value - php

Question

I am creating a listbox box with 2 optional values Ja(Yes) or Nein(No). Additional iam using a default Value which is taken from the database for the record.
Here the code:
<td>
<select name="s_BKAG">
<option selected="selected" ><?php $bkagbruggwert = ''.$abc['BKAG (Brugg)']. ''; if ($bkagbruggwert==1){echo 'Ja';} else {echo 'Nein';};?></option>
<option value="1">Ja</option>
<option value="0">Nein</option>
</select>
</td>
Problem: Now i want that when Yes or No is selected, then id should take their value and if nothing is selected it should take the Value of the preselected default value. But the problem is the variable which i have created has the value "Ja", it does not matter what I'am changing on the formular. I do not know if I overseeing something.
The code of variable defining is here:
$BKAG_Brugg = $_POST['s_BKAG'];
I could take $BKAG_Brugg and define a new variable which i am asking, if the $BKAG_Brugg is "Ja" then set 1 to the new variable. But it's my first project on php and i do not really now how to do the query for the new variable.
Can someone help me with that? i would be thankful for every little help.
regards:
okanog

Answer 1

I think you can do like this:
<select name="s_BKAG">
<option></option>
<?php $bkagbruggwert = $abc['BKAG (Brugg)']; ?>
<option value="1" <?php if($bkagbruggwert == 1) { echo 'selected'; } ?>>Ja</option>
<option value="0" <?php if($bkagbruggwert == 0) { echo 'selected'; } ?>>Nein</option>
</select>
This way, if there is no preselected value, the empty option will be displayed; if there is a preselected value and this value is same as value of any option, it will be selected.
I hope this works for you.

Answer 2

You can do it this way,
Assign the default value to the hidden element
In case, if the user doesn't select one option, then assign the default value from the hidden element
function fetchValue()
{
var selectedValue = document.getElementById("s_BKAG").value;
if(selectedValue == "")
{
selectedValue = document.getElementById("default-value").value;
}
console.log("The selected value is: " + selectedValue);
}
<select id="s_BKAG" name="s_BKAG">
<option value="">None</option>
<option value="1">Ja</option>
<option value="0">Nein</option>
</select>
<input id="default-value" type="hidden" value="<?php echo $abc['BKAG (Brugg)'] ?>" />
<input type="button" value = "Fetch Value" onclick="fetchValue()" />