how to show the value that is selected in drop down menu by the user using javascript

 <select name="place" id="place" onchange="spk();">
<option></option>
<option value="1">California</option>
<option value="2">New York</option>
<option value="3">Las Vegas</option>
<option value="4">Texas</option>
<option value="5">Ohio</option>
</select>

<div id="speak"></div>

<script>
function spk(){
    var b = document.getElementById("place");
    var c = b.options[b.selectedIndex].value; // this shows the selected option's value
    var d = b.options[b.selectedIndex].text; // this shows the selected option's text
    var e = "You have selected ";
    document.getElementById("speak").innerHTML = e.concat(d);
}
</script>

load dynamic forms based on drop down selected by user

hi,
well there are many ways of doing this. i have done it the following way:-
HTML
<div id="spc">
<select id="selectform" onChange="selfo();">
<option value="0">0</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>  
</select>
      <form id="abc" style="display:none">
      <input>
      </form>
      <form id="def" style="display:none">
      <input><input>
      </form>
      <form id="ghi" style="display:none">
      <input><input><input>
      </form>
      </div>

//javascript
    <script>
function selfo()
{
var a = document.getElementById("selectform").value;
if(a == 1){
document.getElementById("abc").style.display = "block";
document.getElementById("def").style.display = "none";
document.getElementById("ghi").style.display = "none";
}
else if(a == 2){
document.getElementById("def").style.display = "block";
document.getElementById("abc").style.display = "none";
document.getElementById("ghi").style.display = "none";
}
else if(a == 3){
document.getElementById("ghi").style.display = "block";
document.getElementById("abc").style.display = "none";
document.getElementById("def").style.display = "none";
}
else if(a == 0){
document.getElementById("spc").style.display = "none";
}
}
    </script>  
  

how to get no of days in the current month(count)?

$da = date('d'); // gets the current day of the month
$mth = date('m');    // gets the current month
$yr = date('Y');   // gets the current year
$daysinmonth = cal_days_in_month(CAL_GREGORIAN,$mth,$yr);

echo $daysinmonth;   // this will echo the total no of days in the current month

now you might also want to use the no of days left in the current month from the current day, here's how that's done:-

$baldays = $daysinmonth - $da;

echo $baldays;    // this would echo out the no of days remaining for the current month to end

how to automatically get the first date of the current month in mysql

there are several ways of doing it. here is how i do it. it just feels simpler this way :)


$mth = date('m');                               // gets the current month
$yr = date('Y');                                   // gets the current year

For example, if i want to run a query to get results between the first day of the current month and today, i would write it like this:-

"SELECT * FROM table WHERE date BETWEEN '$yr-$mth-01' AND CURDATE( )"

how to change all to UPPERCASE in an input box

for a text box, here's the code.

<input type="text" onblur="this.value=this.value.toUpperCase()" name="" placeholder="all of this will be uppercase" />

How to update mysql table ignoring the duplicate fields that are already present

here's how you do it.

INSERT INTO thetable (pageid, name, somefield)
VALUES (1, "foo", "first")
ON DUPLICATE KEY UPDATE (somefield = 'first')

taken from

http://stackoverflow.com/questions/2219786/best-way-to-avoid-duplicate-entry-into-mysql-database

Update one Mysql table with results from another table on a different database

here's how you update one table with results from another database query.


UPDATE
target_database.target_table A                                //database to be updated-target
INNER JOIN source_database.source_table B     //join source database to target
ON B.ProductID = A.ProductID                          //join fields
SET A.Markup = B.Markup                                         //fields to be updated

how to find duplicates in two columns of mysql database table

any one column can have duplicates. but both columns together are unique. this is how you find duplicates

select   columnA,
         columnB,
         count(*)
from     table_name
group by columnA,
         columnB
having   count(*) > 1

how to get the no of days in the current month in php

this function will get the days in the current month

date('t');

how to use the switch statement in php

switch statement can be extremely useful in complex situations.

switch($variable)
{
case "a":
        // run the code if $variable =  a .
break;
case "b":
        // run the code if $variable = b .
break;
case "c":
        // run the code if $variable = c .
break;
default:
        // run the code if $variable is not equal to either a,b or c
}

check existing mysql triggers

SELECT * FROM information_schema.TRIGGERS WHERE TRIGGER_SCHEMA= 'database_name';

OR

SHOW TRIGGERS;

create mysql triggers

table names
testing.name
testing_T.fullname

CREATE TRIGGER addnm AFTER INSERT ON testing
FOR EACH ROW BEGIN
INSERT INTO testing_T SET fullname =  NEW.name;
END;

delimiter |

find duplicate rows in a mysql table

example field = reference
example table = outstandings


" select reference from outstandings group by reference having count(*)>=2 "

pull mysql data as options into select field

<?php
$con = mysql_connect("localhost","username","password"); //connection details
$db = mysql_select_db("databasename",$con); // database details
$qry = mysql_query("SELECT somefield FROM sometable WHERE something = 'somevalue' ")or die(mysql_error()); //actual query
echo "<select name=' '>"; 
echo "<option></option>"; //if you want the first one to be blank
while ($row = mysql_fetch_array($qry))
{
$i = $row['somefield'];
echo "<option>$i</option>";
}
echo "</select>";
mysql_close($con);
?>

how to save MD5 encrypted password into mysql table field

$qry = mysql_query("INSERT INTO table ( username, password ) VALUES ( 'name' , MD5('password')  ")or die(mysql_error());

add or subtract time in php

<?php
date_default_timezone_set('Asia/Dubai');
$rightnow = date('d-m-Y H:i:s');
echo "The time right now is $rightnow";
echo "<br />";
$after = 1200 + time();
$timeafter = date('d-m-Y H:i:s',$after);
echo "The time after 20 minutes will be $timeafter";
echo "<br />";
$before = time() - 1200;
$timebefore = date('d-m-Y H:i:s',$before);
echo "The time 20 minutes ago was $timebefore";
?>

cron job

the following command will fire the script in cron tab

/usr/bin/php -q /home/username/public_html/file.php

file.php is the file that will be fired.
public_html is the folder where the file is saved.
username is your username

how to echo mysql retrieved value into a form as default value

// single field that has been retrieved from mysql database
$qry = mysql_query(" SELECT somefield FROM sometable WHERE something =  'some value'  ")or die(mysql_error());
$result = mysql_fetch_row($qry);
<form action="" method="">
<input type="" name="" value=" <?php echo $result[0]; ?>  ">
</form>
// in case of multiple values retrieved from mysql as a simple array

$qry = mysql_query(" SELECT somefield FROM sometable WHERE something =  'some value'  ")or die(mysql_error());

$result = mysql_fetch_array($qry);

<form action="" method="">

<input type="" name="" value=" <?php echo $result[0]; ?> "> //places the first value from mysql

<input type="" name="" value=" <?php echo $result[1]; ?> "> //places the second value

<input type="" name="" value=" <?php echo $result[2]; ?> "> //places the third value

<input type="" name="" value=" <?php echo $result[3]; ?> "> //places the fourth value and so on

</form>

how to use mysql_num_rows example

$qry = mysql_query(" SELECT * FROM abc WHERE something = 'something' ")or die(mysql_error());
$num = mysql_num_rows($qry);
if($num = 0)
{
// run code here
}
    else
    {
    // run code here
    }

how to use multiple forms on a single page

just name the submit button like this


1st form
<form action="abc.php" method="post"> 
<input type="text" name="abc">
<input type="submit" name="abc">
</form>
2nd form

<form action="abc.php" method="post"> 

<input type="text" name="def">

<input type="submit" name="xyz">

</form>

process the firm results

<?php

if(count($_POST)){

if (!empty($_POST["abc"])){

run your code here for 1st form

}

elseif(!empty($_POST["xyz"])){

run your code here for 2nd form

}

}

?>

you can place as many forms on a single page. As long as the submit name is different, only 1 form will be processed at a time.