How to find if div with specific id exists in jQuery?
I've got a function that appends a <div> to an element on click. The function gets the text of the clicked element and assigns it to a variable called name . That variable is then used as the <div> id of the appended element.
I need to see if a <div> id with name already exists before I append the element but I don't know how to find this.
Here is my code:
$("li.friend").live('click', function() {
name = $(this).text();
// if-statement checking for existence of <div> should go here
// If <div> does not exist, then append element
$("div#chatbar").append("<div class='labels'><div id='" + name + "' style='display:none;'></div>" + name + "</div>");
// Else
alert('this record already exists');
});
This seems pretty straightforward but I'm getting the error “Unexpected end of file while searching for class name”. I have no clue what that means.
if (document.getElementById(name)) {
$("div#" + name).css({bottom: '30px'});
} else {
$("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>");
}
What's more is that I want to be able to delete this element if I close it out which should then remove the div id [name] from the document but .remove() does not do this.
Here is the code for that:
$(".mini-close").live('click', function(){
$(this).parent().remove();
});
I added .mini-close to the append function as a child of .labels so there was a way to close out of the appended <div> if needed. After clicking .mini-close and attempting to click the same name again from li.friends it still finds the div id [name] and returns the first part of my if statement.
You can use .length after the selector to see if it matched any elements, like this:
if($("#" + name).length == 0) {
//it doesn't exist
}
The full version:
$("li.friend").live('click', function(){
name = $(this).text();
if($("#" + name).length == 0) {
$("div#chatbar").append("<div class='labels'><div id='" + name + "' style='display:none;'></div>" + name + "</div>");
} else {
alert('this record already exists');
}
});
Or, the non-jQuery version for this part (since it's an ID):
$("li.friend").live('click', function(){
name = $(this).text();
if(document.getElementById(name) == null) {
$("div#chatbar").append("<div class='labels'><div id='" + name + "' style='display:none;'></div>" + name + "</div>");
} else {
alert('this record already exists');
}
});
Nick's answer nails it. You could also use the return value of getElementById directly as your condition, rather than comparing it to null (either way works, but I personally find this style a little more readable):
if (document.getElementById(name)) {
alert('this record already exists');
} else {
// do stuff
}
Try to check the length of the selector, if it returns you something then the element must exists else not.
if( $('#selector').length ) // use this if you are using id to check
{
// it exists
}
if( $('.selector').length ) // use this if you are using class to check
{
// it exists
}
Use the first if condition for id and the 2nd one for class.
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