What's wrong with my string comparison in javascript?

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Hey everyone,

I'm jumping from C# to Javascript and I'm pretty confused on the string comparison. I recieve an input from an input object with the type set to textbox and parse it like so:

if((Card1 < 1 || Card1 > 10) && (Card1.toLowerCase() !== "a" && Card1.toLowerCase() !== "j" && Card1.toLowerCase() !== "q" && Card1.toLowerCase() !== "k"))
		{
			setColor("red");
			setText("Card #1: You can only use valid cards! (1-10 and J/Q/K/A)");
			return;
		}

It's suppose to perform the action within the if function when it's not an actual play card. A play card can be any number from 1 to 10, or a Jack, Queen, King, Ace. However, right now it seems to be fine with any letter, but not with any number.

What I have tried:

Card1 < 1 || Card1 > 10) &&

to

Card1 < 1 || Card1 > 10) ||

Posted 30-Jun-17 15:36pm

Member 11841791

Updated 30-Jun-17 20:55pm

OriginalGriff

v4

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Ali Majed HA · Answer 1 · 2017-06-30T20:55:00

Hello
I have Improved my solution:

HTML

<input type="text" id="Card1">
<button onclick="myFunction()">Click me</button>

<script>

function myFunction() {
   var a = document.getElementById("Card1").value;
   var b = parseInt(a);
   
   if(1 <= b && b <= 10) { alert("Done!"); }
   
   else {
      switch(a.toLowerCase()){
        case "a": alert("Done!");
          break;
        case "j" : alert("Done!");
          break;
        case "k": alert("Done!");
          break;
        case "q" : alert("Done!");
          break;
        default: alert("Error!");
     }
   }
   
}
</script>

I have tried it and it works fine.

Best Regards