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javascript - Clear text field value in JQuery

I understand this is an easy question but for some reason this just isn't working for me. I have a function that is triggered everytime a drop down menu is changed. Here is the relevant code that is suppose to grab the current value of the text field, if a value exists, clear it that is contained within the .change function:

var doc_val_check = $('#doc_title').attr("value");
    if (doc_val_check.length > 0) {
        doc_val_check == "";
    }

I feel like I am missing something very simple.

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doc_val_check == "";   // == is equality check operator

should be

doc_val_check = "";    // = is assign operator. you need to set empty value

                       // so you need =

You can write you full code like this:

var doc_val_check = $.trim( $('#doc_title').val() ); // take value of text 
                                                     // field using .val()
    if (doc_val_check.length) {
        doc_val_check = ""; // this will not update your text field
    }

To update you text field with a "" you need to try

$('#doc_title').attr('value', doc_val_check); 
// or 
$('doc_title').val(doc_val_check);

But I think you don't need above process.


In short, just one line

$('#doc_title').val("");

Note

.val() use to set/ get value in text field. With parameter it acts as setter and without parameter acts as getter.

Read more about .val()


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