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Question

I am trying to take a string entered by user from a textbox. Check the length of that string and if the string is over a given number perform the slice operation on it.

Here's what I came up with but my code does nothing. Checked console, no errors given.

html:

        <form id="slice">
            Enter a pharse:<input type="text" id="text_box_2"><br>

            <input type="button" value="slice" onclick="Slice()">

            Result: <input type="text" id="slice_result"><br>
        </form>

Javascript function:

function Slice(){
    var UserString = document.getElementById("text_box_2").value;
    var UserStringValue = UserString.length;
    var Result = Userstring.slice(1,6);

    if (UserStringValue > 6){
        document.getElementById("Slice_result").value = Result;
    }
    else{
        alert("Please enter a longer phrase.")
    }
}

what or where did I go wrong?

Answer 1

from cursory reading of your code. it seems caused by this line

var Result = Userstring.slice(1,6);

and also this one

document.getElementById("Slice_result").value = Result

it should be

var Result = UserString.slice(1,6);

and

document.getElementById("slice_result").value = Result

Answer 2

Be mindful of case-sensitivity.

This:

var Result = Userstring.slice(1,6);

Should be using UserString (capital "S") as defined earlier in your code.

Next, the input ID should be all lowercase, slice_result , to match to HTML, but your code uses different casing:

document.getElementById("Slice_result")

Here's a working JSBin with these fixes.

EDIT: As JaromandaX mentioned in the comments, if you want to take the first 6 characters you should use slice(0, 6) .

Answer 3

Usually use of the following

var Value = $('#input_id').val();

will pull the requested information for you.

You can also set up arguments for your slice function and pass in the value when you run onclick();

I'd also note that slice() is a current js function, though your implentation with the capital 'S' is some what different, it may be better practice to change that name a bit.