PHP and HTML select tag - php

I have started with PHP and HTML and would like to execute simple code with three drop-down lists (select tag). But when I make selection from one, the other two selected values disappear. Should I save values when submitting them and then echo. If yes, how can I do it. Sample code will be appreciated.
<?php // formtest_2.php
$name_vid = $name_type = $name_model = "";
if (isset($_POST['vid']))$name_vid=($_POST['vid']);
else $name_vid="no";
if (isset($_POST['type']))$name_type=sanitizeString($_POST['type']);
else $name_type="no";
if (isset($_POST['model']))$name_model=sanitizeString($_POST['model']);
else $name_model="no";
echo <<<_END
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="" selected>Product</option>
<option value = "apple">apple</option>
<option value = "cherry">cherry</option>
<option value = "orange">orange</option>
</select>
<input type="submit"/><br />
<select name="type" size="1">
<option value="" selected>Color</option>
<option value = "green">green</option>
<option value = "red">red</option>
<option value = "orange">orange</option>
</select>
<input type="submit"/><br />
<select name="model" size="1">
<option value="" selected>Model</option>
<option value = "1-a">1-a</option>
<option value = "2-b">2-b</option>
<option value = "3-c">3-c</option>
</select>
<input type="submit"/><br />
</form>
</body>
</html>
_END;
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>

I think you need to re-select the values of the drop downs after submission. The following code would be a fix.
<?php // formtest_2.php
$name_vid = $name_type = $name_model = "(nothing)";
if (isset($_POST['vid']) && $_POST['vid']) $name_vid=($_POST['vid']);
if (isset($_POST['type']) && $_POST['type']) $name_type=sanitizeString($_POST['type']);
if (isset($_POST['model']) && $_POST['model']) $name_model=sanitizeString($_POST['model']);
?>
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="">Product</option>
<option value = "apple" <?php if($name_vid == 'apple') echo 'selected="selected"'; ?>>apple</option>
<option value = "cherry" <?php if($name_vid == 'cherry') echo 'selected="selected"'; ?>>cherry</option>
<option value = "orange" <?php if($name_vid == 'orange') echo 'selected="selected"'; ?>>orange</option>
</select>
<br />
<select name="type" size="1">
<option value="">Color</option>
<option value = "green" <?php if($name_type == 'green') echo 'selected="selected"'; ?>>green</option>
<option value = "red" <?php if($name_type == 'red') echo 'selected="selected"'; ?>>red</option>
<option value = "orange" <?php if($name_type == 'orange') echo 'selected="selected"'; ?>>orange</option>
</select>
<br />
<select name="model" size="1">
<option value="">Model</option>
<option value = "1-a" <?php if($name_model == '1-a') echo 'selected="selected"'; ?>>1-a</option>
<option value = "2-b" <?php if($name_model == '2-b') echo 'selected="selected"'; ?>>2-b</option>
<option value = "3-c" <?php if($name_model == '3-c') echo 'selected="selected"'; ?>>3-c</option>
</select>
<input type="submit"/><br />
</form>
</body>
</html>
<?php
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>
I would not use heredoc syntax ("<<<") to print HTML.

Try this out, i made one submit button, and re selected the values after submit :
<?php
// formtest_2.php
$name_vid = $name_type = $name_model = "";
if (isset($_POST['vid']))
$name_vid = ($_POST['vid']);
else
$name_vid = "no";
if (isset($_POST['type']))
$name_type = sanitizeString($_POST['type']);
else
$name_type = "no";
if (isset($_POST['model']))
$name_model = sanitizeString($_POST['model']);
else
$name_model = "no";
///////////////////
if($name_vid == 'apple')
{
$v1 = 'selected';
}
elseif($name_vid == 'cherry')
{
$v2 = 'selected';
}
elseif($name_vid == 'orange')
{
$v3='selected';
}
////////////////////////
if($name_type == 'green')
{
$t1 = 'selected';
}
elseif($name_type == 'red')
{
$t2 = 'selected';
}
elseif($name_type == 'orange')
{
$t3='selected';
}
///////////////////////
if($name_model == '1-a')
{
$m1 = 'selected';
}
elseif($name_model == '2-b')
{
$m2 = 'selected';
}
elseif($name_model == '3-c')
{
$m3='selected';
}
?>
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form name="fruite_form" action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="" selected>Product</option>
<option <?=$v1?> value = "apple">apple</option>
<option <?=$v2?> value = "cherry">cherry</option>
<option <?=$v3?> value = "orange">orange</option>
</select>
<select name="type" size="1">
<option value="" selected>Color</option>
<option <?=$t1?> value = "green">green</option>
<option <?=$t2?>value = "red">red</option>
<option <?=$t3?>value = "orange">orange</option>
</select>
<select name="model" size="1">
<option value="" selected>Model</option>
<option <?=$m1?> value = "1-a">1-a</option>
<option <?=$m2?>value = "2-b">2-b</option>
<option <?=$m3?>value = "3-c">3-c</option>
</select>
<input name="submitButtom" id="submitButton" type="submit"/><br />
</form>
</body>
</html>
<?
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>
Feel free top add back your submit buttons.
But give each a unique name and also don't forget to name your form, and as a good practice, give then an id too which will be the same as name attribute.
Update: Just to make sure you are really getting a post, since this is your initial question, print this at the end of your code
echo $_POST['vid'] . ' ' . $_POST['type'] . ' ' . $_POST['model'] . '<br/><br/>';
and see if post really holds the value after submission, if you get a value from post, but not from your assigned variables, then check your conditions used at the top to assign your values.
// you need to check if post isset and has an actual value, only than, the varibale should be assigned. Just like what Sithu said.

Related

Focus on HTML Select dropdown option after GET request

So I am making a programme and I am submitting a form to itself. This programme is a very basic calculator as I am new to HTML and PHP. I am trying to make it so that when you submit the form, the Select dropdown will remain on the most recently used operator.
For example, if I make the calculator do '5 + 5', then I want the submitted form to keep the operator dropdown on '+'.
Here is my code:
<?php
// grab the form values from $_HTTP_GET_VARS hash extract($_GET);
// first compute the output, but only if data has been input if(isset($calc) && $operator == "multiply") { // $calc exists as a variable
$prod = $x * $y; } elseif (isset($calc) && $operator == "plus") {
$operator = $plus;
$prod = $x + $y; } elseif (isset($calc) && $operator == "minus") {
$operator = "minus";
$prod = $x - $y; } elseif (isset($calc) && $operator == "divide") {
$sign = "/";
$prod = $x / $y; } else { // set defaults
$x=0;
$y=0;
$prod=0; } ?>
<html> <head>
<title>PHP Calculator Example</title> </head>
<body>
<h3>PHP Calculator (Version 1)</h3>
<p>Multiply two numbers and output the result</p>
<form method="get" action="<?php print $_SERVER['PHP_SELF']; ?>">
<label for="x">x = </label>
<input type="text" name="x" id="x" size="5" value="<?php print $x; ?>"/>
<select name="operator" id="operator">
<option value="plus">+</option>
<option value="minus">-</option>
<option value="divide">/</option>
<option value="multiply">*</option>
</select>
<label for="y">y = </label>
<input type="text" name="y" id="y" size="5" value="<?php print $y; ?>"/>
<input type="submit" name="calc" value="Calculate"/>
</form>
<!-- print the result -->
<?php if(isset($calc)) {
print "<p>x $sign y = $prod</p>";
} ?>
</body> </html>
In order to remain on option selected in the select element
The option has to have an attribute "selected"
<select name="operator" id="operator">
<option <?php if(isset($_GET['operator']) && $_GET['operator'] == "plus"){echo "selected";} ?> value="plus">+</option>
<option <?php if(isset($_GET['operator']) && $_GET['operator'] == "minus"){echo "selected";} ?> value="minus">-</option>
<option <?php if(isset($_GET['operator']) && $_GET['operator'] == "divide"){echo "selected";} ?> value="divide">/</option>
<option <?php if(isset($_GET['operator']) && $_GET['operator'] == "multiply"){echo "selected";} ?> value="multiply">*</option>
</select>
Hope that it will help you.
A possible solution employing javascript would be this
<?php
if(isset($_GET['operator'])) {
?>
<script>document.getElementById("operator").value = '<?=$_GET['operator']?>';</script>
<?php
}
?>

Multiple search value using dropdown list in PHP and MySQL

Html Form:
<form>
<select name="country[]" id="country" multiple>
<option value="any">any</option>
<option value="India">India</option>
<option value="Canada">Canada</option>
<option value="UK">UK</option>
<option value="USA">USA</option>
<option value="Australia">Australia</option>
</select>
</form>
PHP Code
<?php
$country = $_REQUEST['country'];
if($country=="")
$countrysql = "";
else
{
if($country == "Any") $countrysql = "";
else
{
$country = str_replace(",","','",$country);
$countrysql = " and Country in ('$country')";
}
}
$queryString = "SELECT * FROM register where $countrysql";
?>
I have created a form in PHP and I want to search multiple options. I already created table Register and a column Country. I am getting the result If I give single value. If I give multiple I am not getting the result. Please help.
You evaluate in if($country == "Any") the word Any is not equal to any in option <option value="any">any</option>
But I suggest this php code:
<?php
$country="";
$countryError="";
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if (empty($_POST["country"])){
$countryError = "Country is required";
}else{
$country = $_POST["country"];
}
if($country == "Any") {
$queryString = "SELECT * FROM register";
}else{
$queryString = "SELECT * FROM register where Country in ('$country')";
}
// Print the SQL string:
echo $queryString;
}
?>
The html tags:
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
<select name="country" id="country" multiple>
<option value="Any">any</option>
<option value="India">India</option>
<option value="Canada">Canada</option>
<option value="UK">UK</option>
<option value="USA">USA</option>
<option value="Australia">Australia</option>
</select>
<input type="submit" name="submit" value="Submit">
</form>
<span class="error"><?php echo $countryError;?></span>

how to change select tag values based on value coming from database

i want to change tag option based on values coming from database.if value is "1" i want to show different options and different for other values.
<<!DOCTYPE html>
<html>
<head>
<title>select</title>
</head>
<?php
if(isset($_POST['submit']))
{
$number=$_POST['number'];
//echo $number;
if ($number=="1")
{
echo "<select name='subject'>
<option value='1'>chemistry</option>
<option value='2'>Physics</option>
<option value='3'>Biology</option>
<option value='4'>Maths</option></select>"
}
else
{
echo "<select name='subject'>
<option value='5'>english</option>
<option value='6'>computer</option>
<option value='7'>Biology</option>
<option value='8'>Maths</option></select>"
}
?>
<body>
<form method="post" action="select.php">
<input type="text" name="number" value="">
<input type="submit" name="submit" value="submit">
</form>
</select>
</body>
</html>
Because
No closing ; on here <option value='4'>Maths</option></select>"
and here too <option value='8'>Maths</option></select>"
First if() condition missing end }.
So final code is
<!DOCTYPE html>
<html>
<head>
<title>select</title>
</head>
<?php
if(isset($_POST['submit']))
{
$number = $_POST['number'];
//echo $number;
if ( $number == "1" )
{
echo "<select name='subject'>
<option value='1'>chemistry</option>
<option value='2'>Physics</option>
<option value='3'>Biology</option>
<option value='4'>Maths</option></select>";
}
else
{
echo "<select name='subject'>
<option value='5'>english</option>
<option value='6'>computer</option>
<option value='7'>Biology</option>
<option value='8'>Maths</option></select>";
}
}
?>
<body>
<form method="post" action="select.php">
<input type="text" name="number" value="">
<input type="submit" name="submit" value="submit">
</form>
</select>
</body>
</html>
You are missing the ; off of the end of both echos:
if(isset($_POST['submit']))
{
$number=$_POST['number'];
//echo $number;
if ($number=="1")
{
echo "<select name='subject'>
<option value='1'>chemistry</option>
<option value='2'>Physics</option>
<option value='3'>Biology</option>
<option value='4'>Maths</option></select>";
}
else
{
echo "<select name='subject'>
<option value='5'>english</option>
<option value='6'>computer</option>
<option value='7'>Biology</option>
<option value='8'>Maths</option></select>";
}
}
?>
Note: Sorry about poor layout, quick posting of answer!
if(isset($_POST['submit']))
{
$number=$_POST['number'];
//echo $number;
if ($number=="1")
{
echo "<select name='subject'>
<option value='1'>chemistry</option>
<option value='2'>Physics</option>
<option value='3'>Biology</option>
<option value='4'>Maths</option></select>"; //missing ; here
}
else
{
echo "<select name='subject'>
<option value='5'>english</option>
<option value='6'>computer</option>
<option value='7'>Biology</option>
<option value='8'>Maths</option></select>"; //missing ; here
}
} // missing } here

I want to store the onchange value of option and store to a php variable

I want to store the onchange value of option and store to a php variable
<select class="form-control" name="users" >
<option value="#">Please Select Your Employee</option>
<?php while($rows = mysql_fetch_row($res)){ ?>
<option value="<?php echo $rows[0]; ?>">
<?php echo "\r\n $rows[0]";}?>
</option>
</select>
Try This:
<html>
<head>
<script type="text/javascript">
function myfunction(){
a = document.getElementById('myselect').value;
location.href="?a="+a;
}
</script>
</head>
<body>
<select id="myselect" onchange="myfunction()">
<option value="10" <?php if($_GET['a']== 10 ) echo "selected"; ?> > value 10 </option>
<option value="20" <?php if($_GET['a']== 20 ) echo "selected"; ?> > value 20 </option>
<option value="30" <?php if($_GET['a']== 30 ) echo "selected"; ?> > value 30 </option>
</select>
<?php
if (isset($_GET['a'])) {
$val = $_GET['a'];
echo $val;
}
else{
$val = 0;
echo $val;
}
?>
</body>
</html>

Post back the data if validation fails for "Select"

Once submitted selected option, the data is not stored.
just want to know how to post back the data if validation fails
The following line doesnt really work for me.
<select id="numbers" name="numbers" value="<?php echo (isset($_POST['numbers'])) ? $_POST['numbers'] : " "; ?>"/>
if someone could give me a hand?
Many thanks, here is my code
<?php
if(isset($_POST['numbers']) &&($_POST['fruits']) && $_POST['numbers'] != "null" && $_POST['fruits'] !== "null")
{
echo "Thank you!";
} elseif (isset($_POST['numbers']) && $_POST['numbers'] = "null") {
echo "you forgot to choose a number";
}
elseif(isset($_POST['fruits']) && $_POST['fruits'] = "null")
{
echo "you forgot to choose fruit name";
}
?>
<form id="form" name="form" method="post" action="">
<label for="expiry">Select</label>
<select id="numbers" name="numbers" value="<?php echo (isset($_POST['numbers'])) ? $_POST['numbers'] : " "; ?>"/>
<option value="null" selected="selected">-</option>
<option value="01">01</option>
<option value="02">02</option>
<option value="03">03</option>
</select>
<select id="fruits" name="fruits" value="<?php echo (isset($_POST['fruits']))? $_POST['fruits'] : ''; ?>"/>
<option value="null" selected="selected">-</option>
<option value="Apple">Apple</option>
<option value="Banana">Banana</option>
<option value="Pear">Pear</option>
</select>
<input type="submit" value="Send" />
</form>
Solved it, Maybe not a best way, but at least got it sorted:
<?php
$item = null; #
$itemyear = null;
if(isset($_POST['numbers'])){
$item = $_POST['numbers'];
}
if(isset($_POST['fruits'])){
$itemyear = $_POST['fruits'];
}
if(isset($item) && isset($itemyear) && $item != "null" && $itemyear !== "null")
{
echo "Thank you!";
} elseif ($item == "null") {
echo "you forgot to choose a number";
}
elseif($itemyear == "null")
{
echo "you forgot to choose fruit name";
}
?>
<form id="form" name="form" method="post" action="">
<label for="expiry">Select</label>
<select id="numbers" name="numbers" />
<option value="null" selected="selected">-</option>
<option value="01" <?php if($item == '01'): echo "selected='selected'"; endif; ?>>01</option>
<option value="02" <?php if($item == '02'): echo "selected='selected'"; endif; ?>>02</option>
<option value="03" <?php if($item == '03'): echo "selected='selected'"; endif; ?>>03</option>
</select>
<select id="fruits" name="fruits" />
<option value="null" selected="selected">-</option>
<option value="Apple"<?php if($itemyear == 'Apple'): echo "selected='selected'"; endif; ?> >Apple</option>
<option value="Banana"<?php if($itemyear == 'Banana'): echo "selected='selected'"; endif; ?>>Banana</option>
<option value="Pear"<?php if($itemyear == 'Pear'): echo "selected='selected'"; endif; ?>>Pear</option>
</select>
<input type="submit" value="Send" />
</form>
<?php
echo $item ."-". $itemyear;
?>
the PHP isset() function returns either true or false (depending on whether the input is.. well... set.
You would want to use this:
value='<?php echo (isset($_POST['numbers'])) ? $_POST['numbers'] : ""; ?>
You can't set a value attribute on a <select>. You have to find the correct <option> and set its selected attribute. Personally, I put a data-default attribute on the <select> and then use JavaScript to loop through the options and find the right one.
Oh now I see.
I don't know what the usual thing to do is but one way is to put all the data as a query string when you redirect the user back. The reason why it doesn't stay in the $_POST global is because it's only kept on the page you post to then it's gone.
So when you redirect the user back
if(validationFailed)
{
header("Location: page.php?data=example");
}
The data can then be retrieved in page.php by using
$data = $_GET['data']; // contains "example"

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