How to check if some element has attribute “name” starts with something, not “value”

Question

I\'m going to use various data attributes names start with for example \"data-mo-\".

Assume I have these elements:

Answer 1

If I get it right you want to check for data-mo so I have tried something to make this work;

function getData(index){
	if(index[0].indexOf("mo") !== -1)
    	return true
        
    return false
}

$.each($("span"), function(i,index){
	var objectKey = Object.keys($(this).data());
	if(getData(objectKey)){
    	$(this).addClass("valid")
    } else {
    	$(this).addClass("not-valid")
    }
    	
})

.valid {
    color: green
}
.not-valid {
    font-weight: bold;
    color: red;
    text-decoration: line-through
}

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