Question

How can i emulate the backspace key function when i press the up arrow?

This is what i have so far and its not working :

if ( e.keycode === 38 ) {
        e.preventDefault();
        $(e.target).trigger({
            type: "keypress",
            which: 8
        };

Answer 1

Description

You can use jQuery’s keyup method to get this done.
As far as i understand you want to remove the last char in the field.
Checkout my sample and this jsFiddle Demonstration

Sample

$("input").keyup(function(e) {
     if (e.which=== 38 ) {
        e.preventDefault();
        var value = $("input").val();
        var newValue = $("input").val().substring(0, value.length-1);
        $("input").val(newValue);
     }
});
​

More Information

• jQuery.keyup()
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