Sending FormData with jQuery.ajax() | Matt

Unfortunately, it’s not as easy as setting the data attribute to the FormData instance; jQuery runs anything that isn’t a string through jQuery.param() to serialize the objects keys into key1=a&key2=b etc; running FormData through this doesn’t end too nicely.

However one of jQuery.ajax()‘s many options is processData, which allows you to turn off this behaviour by setting it’s value to false. So, to use FormData with jQuery.ajax() it’s as simple as:

var formData = new FormData($('form')[0]); // Create an arbitrary FormData instance    jQuery.ajax('/endpoint.php', {      processData: false,      contentType: false,      data: formData  });

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