How to put a display a default image if no src specified?

I have HTML from a database that sometimes give no src values like this:

<img class="some-image" src=""开发者_StackOverflow>

How do I supply it with an image if there is no src value like above?

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You can test the src attribute to see if it's empty:

$('img[src=""]').attr("src", "default.jpg");

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$('img[src=""]').attr('src', 'urltoimage');

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You can define it on the css class as background for the tag and overwrite it with the src tag where available. Are you meaning this?