Error Handling

coderzaman · coderzaman · commit ce48e3b258f4 · 2024-09-03T20:26:51.000+06:00
diff --git a/12. Error Handling/index.html b/12. Error Handling/index.html
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <h1 id="showMessage"></h1>
+    <!-- link javacript file -->
+     <script src="js/script.js"></script>
+  
+</body>
+</html>
diff --git a/12. Error Handling/js/script.js b/12. Error Handling/js/script.js
@@ -0,0 +1,70 @@
+// JavaScript Errors
+// Throw, and Try...Catch...Finally
+// The try statement defines a code block to run (to try).
+// The catch statement defines a code block to handle any error.
+// The finally statement defines a code block to run regardless of the result.
+// The throw statement defines a custom error.
+
+// Errors Will Happen!
+// When executing JavaScript code, different errors can occur.
+// Errors can be coding errors made by the programmer, errors due to wrong input, and other unforeseeable things.
+
+// In this example we misspelled "alert" as "adddlert" to deliberately produce an error:
+
+// If we add try catch block the program run before and after error occurs. But not use try catch where an be possible to cause error next programm can not be run
+
+
+console.log("Bismillah");
+try {
+    addAlert("Welcome Guest!");
+}catch(err){
+    console.log(err.message);
+}
+
+console.log("Hi thank you");
+
+
+// The throw Statement
+// The throw statement allows you to create a custom error.
+// Technically you can throw an exception (throw an error).
+// The exception can be a JavaScript String, a Number, a Boolean or an Object:
+
+let input = prompt("Enter a Number: ");
+
+try{
+    if(input < 18) throw "To Young";
+    else if(input > 100) throw "You do not need to vote! Rest in House";
+}catch(err){
+    console.log(err);
+}
+
+// The finally Statement
+// The finally statement lets you execute code, after try and catch, regardless of the result:
+
+
+// Syntax
+// try {
+//   Block of code to try
+// }
+// catch(err) {
+//   Block of code to handle errors
+// }
+// finally {
+//   Block of code to be executed regardless of the try / catch result
+// }
+
+try{
+    addAlert("");
+}catch(err){
+    console.log(err.message);
+}finally{
+    console.log("Do't Care Error or NOt");
+}
+
+try{
+   console.log("Finally Check");
+}catch(err){
+    console.log(err.message);
+}finally{
+    console.log("Do't Care Error or NOt");
+}
