Javascript Bind on Blur, Both 'if indexOf' and 'else' Performed
HTML
<!-- Contents of div #1 -->
<form id="6hgj3y537y2biacb">
<label for="product_calendar" class="entry_label">Calendar</label>
<input type="text" name="product_calendar" class="entry" value="" />
</form>
<form id="pyc2w1fs47mbojez">
<label for="product_calendar" class="entry_label">Calendar</label>
<input type="text" name="product_calendar" class="entry" value="" />
</form>
<form id="kcmyeng53wvv29pa">
<label for="product_calendar" class="entry_label">Calendar</label>
<input type="text" name="product_calendar" class="entry" value="" />
</form>
<!-- Contents of div #2 -->
<div id="calendar_addRemove"> <!-- CSS >> display: none; -->
<div id="calendar_add">
<label for="calendar_add" class="calendar_addLabel">Add Occurrence</label>
<input type="text" name="calendar_add" class="calendar_addInput" value=""/>
</div>
<div id="calendar_remove">
<label for="calendar_remove" class="calendar_removeLabel">Remove Occurrence</label>
<input type="text" name="calendar_remove" class="calendar_removeInput" value=""/>
</div>
</div>
Javascript
// Complete behavioral script
$(function() {
$('input[name=product_calendar]').css({ 'color': '#5fd27d', 'cursor': 'pointer' }).attr({ 'readonly': 'readonly' }); // Additional formatting for specified fields
$('input[name=product_calendar]').focus(function() { // Focus on any 'input[name=product_calendar]' executes function
var product_calendar = $(this); // Explicit declaration
var attr_val = $(product_calendar).attr('value');
$('#calendar_addRemove input').attr({ 'value': '' }); // Clear input fields
$('#calendar_addRemove').fadeIn(500, function() { // Display input fields
$('input[name=calendar_add]').blur(function() { // After value entered, action occurs on blur
alert(开发者_如何转开发'Blur'); // Added for testing
var add_val = $('input[name=calendar_add]').attr('value');
if (add_val != '') {
alert('Not Blank'); // Added for testing
var newAdd_val = attr_val + ' ' + add_val;
$(product_calendar).attr({ 'value': newAdd_val });
$('#calendar_addRemove').fadeOut(500);
}
else {
alert('Blank'); // Added for testing
$('#calendar_addRemove').fadeOut(500);
}
});
$('input[name=calendar_remove]').blur(function() { // After value entered, action occurs on blur
alert('Blur'); // Added for testing
var remove_val = $(this).attr('value');
if (remove_val != '') {
alert('Not Blank'); // Added for testing
if (attr_val.indexOf(remove_val) != -1) {
alert('Eval True'); // Added for testing
var newRemove_val = attr_val.replace(remove_val, '');
$(product_calendar).attr({ 'value': newRemove_val });
$('#calendar_addRemove').fadeOut(500);
}
else {
alert('Eval False'); // Added for testing
$('#calendar_remove').append('<p class="error">Occurrence Not Found</p>');
$('.error').fadeOut(1500, function() { $(this).remove(); });
}
}
else {
alert('Blank'); // Added for testing
$('#calendar_addRemove').fadeOut(500);
}
});
});
});
});
I've added a few alerts to see the order this script is performing in. When I enter 1234
into input[name=calendar_add]
and blur, the alerts come up as expected. Then, when I proceed and enter 1234
into input[name=calendar_remove]
and blur, this script throws up alerts in the following order: Blur, Not Blank, Eval False, Blur, Not Blank, Eval True - If I repeat this process, the occurrence of my alerts double every time (both add and remove), however keeping the same order (as if in sets).
I think the issue is multiple value re-declaration of the variable attr_val
in the DOM, but I'm not quite sure how to revise my script to alleviate this issue.
It doesn't. That is not possible.
So, there are some possible reasons that it might seem so:
The code that actually runs doesn't look like that. It might be an older version that is cached, or you are looking in the wrong file.
The code runs more than once, that way both execution branches may run. (Although I can't really see any possibility for that here.)
You are misinterpreting the result, and whatever you see that leads to the conclusion that both branches have to be executed, is in fact caused by some other code.
You could use a debugger to set breakpoints in the code. Set one breakpoint before the condition, and one in each branch. Then you will see if the code runs twice, once or not at all.
Edit:
The alerts that you added to the code shows that the event is actually called twice, and the first time the values are not what you think that they are.
Add some code to try to find out where the event is invoked from. Catch the event object by adding it to the function signature: .blur(function(e) {
. Then you can use e.currentTarget to get the element that triggered the event, and display some attributes from it (like it's id) to identify it.
Edit 2:
I am curios about this line:
$(product_calendar).attr({ value: newRemove_val });
Do you create the variable product_calendar
somewhere, or did you mean:
$('input[name=product_calendar}').attr({ value: newRemove_val });
Edit 3:
Seeing the complete code, the cause of the double execution is clear. You are adding even handlers inside an event handler, which means that another handler is added every time.
The reason for attr_val
not working properly is because it's created as a local variable in one function, and then unsed in another function.
Add the blur handlers from start instead, and they occur only once. Declare the variable outside the function.
Some notes:
- You can use the
val
function instead of accessing thevalue
attribute using theattr
function. - When you assign
$(this)
toproduct_calendar
, it's a jQuery object. You don't have to use$(product_calendar)
. - The removal doesn't match complete values, so you can add
12
and2
, then remove2
and you get1
and2
left.
(this is a dummy text, because you can't have a code block following a list...)
// Complete behavioral script
$(function() {
// declare variables in outer scope
var attr_val;
var product_calendar;
$('input[name=product_calendar]')
.css({ 'color': '#5fd27d', 'cursor': 'pointer' })
.attr('readonly', 'readonly') // Additional formatting for specified fields
.focus(function() { // Focus on any 'input[name=product_calendar]' executes function
product_calendar = $(this); // Explicit declaration
attr_val = product_calendar.val();
$('#calendar_addRemove input').val(''); // Clear input fields
$('#calendar_addRemove').fadeIn(500); // Display input fields
});
$('input[name=calendar_add]').blur(function() { // After value entered, action occurs on blur
var add_val = $(this).val();
if (add_val != '') {
product_calendar.val(attr_val + ' ' + add_val);
}
$('#calendar_addRemove').fadeOut(500);
});
$('input[name=calendar_remove]').blur(function() { // After value entered, action occurs on blur
var remove_val = $(this).val();
if (remove_val != '') {
if (attr_val.indexOf(remove_val) != -1) {
product_calendar.val(attr_val.replace(remove_val, ''));
$('#calendar_addRemove').fadeOut(500);
} else {
$('#calendar_remove').append('<p class="error">Occurrence Not Found</p>');
$('.error').fadeOut(1500, function() { $(this).remove(); });
}
} else {
$('#calendar_addRemove').fadeOut(500);
}
});
});
OK, I think I understand the issue now.
Every time you do a focus on the product_calendar
elements, you do a fadeIn
on the #calendar_addRemove
element. Every time you do that fadeIn
, you use its callback to bind new blur handlers to the calendar_add
and calendar_remove
elements. That means that over time, those elements will have multiple blur handlers (all executing the same logic.) That can't be what you want.
In the script below, I've pulled out the nested handlers so that they're only bound once to each element. Note that:
product_calendar
is declared (asnull
) at the top of the anonymous function, and then updated by the focus handler on theproduct_calendar
element. I think this results in correct behavior.attr_val
is declared and assigned locally in both of the blur handlers. Again, I think this results in the correct behavior: If you were to declare it outside of the blur handlers (asproduct_calendar
is declared), then you might accidentally use old values when you access it.
I'm still not sure exactly how this code is supposed to function, but this script performs in a way that I'd consider "reasonable".
(By the way, production code should probably allow for whitespace at the beginning and end of the input strings.)
$(function() {
var product_calendar = null;
$('input[name=product_calendar]').css({ 'color': '#5fd27d', 'cursor': 'pointer' }).attr({ 'readonly': 'readonly' }); // Additional formatting for specified fields
$('input[name=calendar_add]').blur(function() { // After value entered, action occurs on blur
alert('Blur'); // Added for testing
var add_val = $('input[name=calendar_add]').attr('value');
if (add_val != '') {
alert('Not Blank'); // Added for testing
var attr_val = $(product_calendar).attr('value');
var newAdd_val = attr_val + ' ' + add_val;
$(product_calendar).attr({ 'value': newAdd_val });
$('#calendar_addRemove').fadeOut(500);
}
else {
alert('Blank'); // Added for testing
$('#calendar_addRemove').fadeOut(500);
}
});
$('input[name=calendar_remove]').blur(function() { // After value entered, action occurs on blur
alert('Blur'); // Added for testing
var remove_val = $(this).attr('value');
if (remove_val != '') {
alert('Not Blank'); // Added for testing
var attr_val = $(product_calendar).attr('value');
if (attr_val.indexOf(remove_val) != -1) {
alert('Eval True'); // Added for testing
var newRemove_val = attr_val.replace(remove_val, '');
$(product_calendar).attr({ 'value': newRemove_val });
$('#calendar_addRemove').fadeOut(500);
}
else {
alert('Eval False'); // Added for testing
$('#calendar_remove').after('<p class="error">Occurrence Not Found</p>');
$('.error').fadeOut(1500, function() { $(this).remove(); });
}
}
else {
alert('Blank'); // Added for testing
$('#calendar_addRemove').fadeOut(500);
}
});
$('input[name=product_calendar]').focus(function() { // Focus on any 'input[name=product_calendar]' executes function
product_calendar = $(this);
$('#calendar_addRemove input').attr({ 'value': '' }); // Clear input fields
$('#calendar_addRemove').fadeIn(500);
});
});
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