revision:
The localeCompare() method compares two strings in the current locale. The localeCompare() method returns sort order -1, 1, or 0 (for before, after, or equal). The current locale is based on the language settings of the browser.
string.localeCompare(compareString)
Parameters:
compareString : required. The string to compare with.
<p>localeCompare() returns one of 3 numbers indicating the sort order.</p>
<ul>
<li>-1 if sorted before</li>
<li>1 if sorted after</li>
<li>0 if equal</li>
</ul>
<p>Compare "ab" with "cd":</p>
<p id="demo"></p>
<script>
let text1 = "ab";
let text2 = "cd";
let result = text1.localeCompare(text2);
document.getElementById("demo").innerHTML = result;
</script>
localeCompare() returns one of 3 numbers indicating the sort order.
Compare "ab" with "cd":
<div>
<p>localeCompare() returns one of 3 numbers indicating the sort order.</p>
<ul>
<li>-1 if sorted before</li>
<li>1 if sorted after</li>
<li>0 if equal</li>
</ul>
<p>Compare "ab" with "cd":</p>
<p id="compare-1"></p>
<p id="compare-2"></p>
</div>
<script>
let text1 = "ab";
let text2 = "cd";
document.getElementById("compare-1").innerHTML = "text 1 : " + text1 + " ; " + "text 2 : "+ text2;
let result = text1.localeCompare(text2);
document.getElementById("compare-2").innerHTML = "result : " + result;
</script>
localeCompare() returns one of 3 numbers indicating the sort order.
Compare "cd" with "ab":
<div>
<p>localeCompare() returns one of 3 numbers indicating the sort order.</p>
<ul>
<li>-1 if sorted before</li>
<li>1 if sorted after</li>
<li>0 if equal</li>
</ul>
<p>Compare "cd" with "ab":</p>
<p id="compare-3"></p>
<p id="compare-4"></p>
</div>
<script>
let text3 = "cd";
let text4 = "ab";
document.getElementById("compare-3").innerHTML = "text 3 : " + text3 + " ; " + "text 4 : "+ text4;
let result1 = text3.localeCompare(text4);
document.getElementById("compare-4").innerHTML = "result : " + result1;
</script>
localeCompare() returns one of 3 numbers indicating the sort order.
Compare "ab" with "ab":
<div>
<p>localeCompare() returns one of 3 numbers indicating the sort order.</p>
<ul>
<li>-1 if sorted before</li>
<li>1 if sorted after</li>
<li>0 if equal</li>
</ul>
<p>Compare "ab" with "ab":</p>
<p id="compare-5"></p>
<p id="compare-6"></p>
</div>
<script>
let text5 = "ab";
let text6 = "ab";
document.getElementById("compare-5").innerHTML = "text 5 : " + text5 + " ; " + "text 6 : "+ text6;
let result2 = text5.localeCompare(text6);
document.getElementById("compare-6").innerHTML = "result : " + result2;
</script>