Set loading image using jQuery's ajaxSetup() method

The following is a simple jQuery code snippet that uses the ajaxSetup() method to set up the loading image so that the loading image is displayed every time an AJAX request is sent and the loading image is hidden when the request returns. Since the .load() function seems to ignore (or override) the complete function, the same code for the complete and success functions is included. Demo

Code

$.ajaxSetup({
  beforeSend: function() {
    $('#general-ajax-load').fadeIn();
  },
  complete: function() {
    $('#general-ajax-load').fadeOut();
  },
  success: function() {
    $('#general-ajax-load').fadeOut();
  }
});

FAQs about jQuery.ajaxSetup() (FAQ)

What is the main purpose of jQuery.ajaxSetup()?

jQuery.ajaxSetup() method is mainly used to set default values ??for future AJAX requests. This is a global method that affects all AJAX calls and is therefore usually used to define a set of default options that will be applied to all subsequent AJAX requests. This is especially useful when you want to apply the same settings (such as timeout or cache) in multiple AJAX requests.

How is jQuery.ajaxSetup() different from jQuery.ajax()?

While jQuery.ajaxSetup() and jQuery.ajax() are used to handle AJAX requests, their purpose is different. jQuery.ajaxSetup() is used to set default values ??for future AJAX requests, while jQuery.ajax() is used to make a single AJAX request. The settings defined in jQuery.ajaxSetup() will be applied to all AJAX requests, including those issued with jQuery.ajax().

Can I override the settings defined in jQuery.ajaxSetup()?

Yes, you can override the settings defined in jQuery.ajaxSetup() for a single AJAX request. When you make an AJAX request using jQuery.ajax() , you can specify options that apply only to that specific request. These options will take precedence over the default values ??set in jQuery.ajaxSetup() .

What common options can be set in jQuery.ajaxSetup()?

Some common options that can be set in jQuery.ajaxSetup() include "async", "cache", "contentType", "data", "dataType", "global", "ifModified", "jsonp", "jsonpCallback", "password", "processData", "scriptCharset", "timeout", "traditional", "type", "url", "username", and "xhr". Each of these options plays a specific role in controlling how AJAX requests are made and how responses are handled.

Can I use jQuery.ajaxSetup() to set the loading image?

While jQuery.ajaxSetup() itself does not provide the option to directly set up the image loading, you can do this using the global AJAX event handler. For example, you can use the "ajaxStart" event to display the loaded image at the start of an AJAX request and hide the image using the "ajaxStop" event when the request is completed.

Can I use jQuery.ajaxSetup() with other jQuery AJAX methods?

Yes, the settings defined in jQuery.ajaxSetup() apply to all jQuery AJAX methods, including jQuery.get(), jQuery.post(), and jQuery.load(). The default settings are used unless overridden in a single AJAX request.

How to deal with errors in jQuery.ajaxSetup()?

You can handle errors in jQuery.ajaxSetup() by defining the "error" option. This option takes a function that will be called if the AJAX request fails. This function can take three parameters: a jqXHR object, a string describing the error type, and (if it happens) an optional exception object.

Can I set the default header for AJAX requests using jQuery.ajaxSetup()?

Yes, you can set default headers for all AJAX requests using the "headers" option in jQuery.ajaxSetup() . The "headers" option takes an object where each key-value pair represents a header name and its value.

Is it recommended to use jQuery.ajaxSetup()?

While jQuery.ajaxSetup() can be used to set the default AJAX options, it should be used with caution as it affects all AJAX requests. If you only need to set options for a specific request, it is usually better to set them directly in a jQuery.ajax() call or other AJAX methods.

Can I unset or reset the default value set in jQuery.ajaxSetup()?

Yes, you can unset or reset the default value set in jQuery.ajaxSetup() by calling the method with an empty object. This will effectively clear all previously set default options.

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