previous value

[smiley22]

I would like to know how to check the current value and the previous value entered by user before changes.

for example, the form will allow user to enter customer number. The first time user enter 10 then change to 22

customer number : 10 -> change to 22

how do I get the previous value which is 10 in this case


thanks...

[gits]

hi ...

in that case you have to store the values in your app ... it is a good idea to write a kind of utility-function for that purpose ... one that loops through your desired formelements and stores the values of each element within an content-object or something like this. it should create something like the following:

// content object
var content_obj = {
    element_name_or_id_1: value,
    element_name_or_id_2: value,
    element_name_or_id_3: value,
    element_name_or_id_4: value
    // as much elements as you need
};
 

later ... probably in the onchange-event of your elements you check the newvalue against the one of your content-object.

// refer properly to element_name_or_id_1 (here we use the id)
var ele = document.getElementById('element_name_or_id_1');
if (ele.value != content_obj['element_name_or_id_1']) {
     // or whatever you want to check
}
 

you may set the content_obj[element_name_or_id_1] to newvalue when the check was successful or call your utility-function again so that it stores the actual values and you may compare again old- and newvalues ...

thats the idea ... hope it helps ...

kind regards ...

[dmjpro]

I would like to know how to check the current value and the previous value entered by user before changes.

for example, the form will allow user to enter customer number. The first time user enter 10 then change to 22

customer number : 10 -> change to 22

how do I get the previous value which is 10 in this case


thanks...

see onchange event fired when the an element loses focus and the value changed.
so on firing this event the updated value we can get , not the previous value.
so try this ......

<input type = text onfocus = fun1(this) onblur = fun2(this)>
 

var prev_value,cur_value;
function fun1(val)
{
prev_value = val.value;
}
function fun2(val)
{
cur_value = val.value;
}
 

i hop it ll help u.
best of luck

kind regards,
dmjpro.

[gits]

see onchange event fired when the an element loses focus and the value changed.
so on firing this event the updated value we can get , not the previous value.
so try this ......

<input type = text onfocus = fun1(this) onblur = fun2(this)>
 

var prev_value,cur_value;
function fun1(val)
{
prev_value = val.value;
}
function fun2(val)
{
cur_value = val.value;
}
 

i hop it ll help u.
best of luck

kind regards,
dmjpro.

hi

... the focus event is a good point to store the value, your'e right, but onblur is not ... onchange is even better ... because you may change the value with pressing enter and then the field don't loose focus and nothing blurs ...

kind regards ...

[dmjpro]

hi

... the focus event is a good point to store the value, your'e right, but onblur is not ... onchange is even better ... because you may change the value with pressing enter and then the field don't loose focus and nothing blurs ...

kind regards ...

that means u say if the value changed without changing it's value then onchange event firing.
right???
i just need confirmation.

kind regards,
dmjpro.

[gits]

that means u say if the value changed without changing it's value then onchange event firing.
right???
i just need confirmation.

kind regards,
dmjpro.

no ... you change the value and press enter ... then no blur-event fires but the onchange do!

kind regards ...

[dmjpro]

no ... you change the value and press enter ... then no blur-event fires but the onchange!

kind regards ...

oh i seee ..... thanksssssss

kind regards,
dmjpro.