adding html textbox value in php variable

Question

I want to sum values in a php variable from html text box my php code is as under

$total = 0;
$val2 = $_POST['val1'];
$total += val2;
echo "Sum of value is ". $total;

This is my HTML:

<form action="add.php" method="post" >
  <input type="text" name="val1" />
  ...
  ...

'<form action="add.php" method="post" >' '<input type="text" name="val1" />' — irfan spi
– irfan spi, Commented Nov 26, 2015 at 11:36
when i give first value in text box it shows the first value ,but as i give the value second time it doesnot sum the previous value with new one and display only last value given — irfan spi
– irfan spi, Commented Nov 26, 2015 at 11:37
Because PHP is a server side programming language and it runs at first. next time u will need to refresh the page — Rahul
– Rahul, Commented Nov 26, 2015 at 11:43

Abhishek Sharma · Accepted Answer · 2015-11-26 11:48:34Z

2

use Session

session_start();
$total = 0;
$val2 = $_POST['val1'];
$_SESSION["total"]+= $val2;
echo "Sum of value is ". $_SESSION["total"];

A session is a way to store information (in variables) to be used across multiple pages

edited Nov 26, 2015 at 11:48

answered Nov 26, 2015 at 11:40

Abhishek Sharma

6,6241 gold badge17 silver badges20 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

William Madede Over a year ago

What will happen if the $_SESSION["total "] is not set ..? especially when it runs for the first time? @Rahautos

irfan spi Over a year ago

i tried it but it doesn't working ,it is showing "sum of value is val2 " every time i enter a value in text box

Abhishek Sharma Over a year ago

session_start(); $total = 0; $val2 = $_POST['val1']; $_SESSION["total"]+= $val2; echo "Sum of value is ". $_SESSION["total"];

William Madede · Accepted Answer · 2015-11-26 11:54:23Z

1

Use sessions;

session_start();
$val2 = $_POST['val1'];
$total = 0;
if(isset($_SESSION['prev_sum'])){
    $total = $_SESSION['prev_sum'] + $val2;
}else{
    $total += $val2;
}
$_SESSION['prev_sum'] = $total;

echo "Sum of value is ". $total;

edited Nov 26, 2015 at 11:54

answered Nov 26, 2015 at 11:37

William Madede

7234 silver badges8 bronze badges

2 Comments

irfan spi Over a year ago

i tried this code but it is not sum the second value given in text box .

irfan spi Over a year ago

it set the $total value to 0 when i enter value in text box next time

Saani · Accepted Answer · 2015-11-26 11:41:12Z

0

$total+=$val2 refers to $total = $total + $val2 so the values are being summed up in the variable $total instead of $val2. So replace $val2 in echo statement with $total.

answered Nov 26, 2015 at 11:41

Saani

79210 gold badges29 silver badges75 bronze badges

Comments

Muhammad H Tahir · Accepted Answer · 2015-11-26 11:46:02Z

0

you have to use sessions or database(which is not suitable for your current problem) for this because http is stateless protocol i-e it cannot maintain its state so as soon as new request originates all the variables set to its default values

session_start();
$sum= 0;
$val2 = $_POST['val1'];
$_SESSION["sum"]+= val2;
echo "Sum of value is ". $_SESSION["sum"];

answered Nov 26, 2015 at 11:46

Muhammad H Tahir

1,0491 gold badge15 silver badges28 bronze badges

Comments

Ashish Choudhary · Accepted Answer · 2015-11-26 11:50:35Z

0

It should be something like

session_start();
$val1 = isset($_SESSION['val2']) ? $_SESSION['val2'] : 0 ;
$val2 = $_POST['val2'];
$total = $val1 + $val2;
$_SESSION['val2'] = $total;
echo "Sum of value is ". $total;

AND

<form action="add.php" method="post" >
    <input type="text" name="val1" value="<?php echo $_POST['val1'] ?>" />
    <input type="text" name="val2" />
....

edited Nov 26, 2015 at 11:50

answered Nov 26, 2015 at 11:37

Ashish Choudhary

2,0341 gold badge20 silver badges26 bronze badges

3 Comments

irfan spi Over a year ago

it showing the value i entered in text box .but when i enter next value in text box it does't sum the second value in $total variable

irfan spi Over a year ago

no sir i want to use one text box ,every time i enter a value in text box it should be sum in $total variable and shows the result new value

Ashish Choudhary Over a year ago

In that case, You can use the solution provided by `William Madede. use session to store old value. I have editied the answer. please have a look

Collectives™ on Stack Overflow

adding html textbox value in php variable

5 Answers 5

3 Comments

2 Comments

Comments

Comments

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

3 Comments

2 Comments

Comments

Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related