05_typescript/uebungen/u01_erkennung-typenfehlern/src/main.ts

@@ -1,5 +1,5 @@
-function calculateDiscount(price: number, discount: string): number {
-  return price - parseFloat(discount);
+function calculateDiscount(price: number, discount: number): number {
+  return price - discount;
 }
 
 const finalPrice = calculateDiscount(100, 10);

05_typescript/uebungen/u02_user-email/src/main.ts

@@ -1,6 +1,25 @@
-const user = {
-  name: 'John Doe',
-  age: 30,
-};
+{
+  interface User {
+    name: string;
+    age: number;
+    email?: string; // optional property ?
+  }
 
-console.log(user.email.toLowerCase());
+  const user: User = {
+    name: 'John Doe',
+    age: 30,
+    email: 'john@example.com',
+  };
+
+  const trainer: User = {
+    name: 'Philippe Torrel',
+    age: 42,
+  };
+
+  // 'trainer.email' is possibly 'undefined'.
+  // trainer.email.toLowerCase();
+  trainer.email?.toLowerCase();
+  console.log(user.email?.toLowerCase());
+
+  console.log(user.email ? user.email.toLowerCase() : 'No existing mail');
+}

05_typescript/uebungen/u03_vehicle-interface/assets/js/bundle.js

@@ -0,0 +1,34 @@
+(() => {
+  var __getOwnPropNames = Object.getOwnPropertyNames;
+  var __commonJS = (cb, mod) => function __require() {
+    try {
+      return mod || (0, cb[__getOwnPropNames(cb)[0]])((mod = { exports: {} }).exports, mod), mod.exports;
+    } catch (e) {
+      throw mod = 0, e;
+    }
+  };
+
+  // src/main.ts
+  var require_main = __commonJS({
+    "src/main.ts"() {
+      var myCar = {
+        startEngine: (key) => {
+          console.log(`Engine started with key: ${key}`);
+          return true;
+        },
+        drive: (speed) => {
+          return `Driving at ${speed} km/h`;
+        }
+      };
+      function operateVehicle(vehicle) {
+        if (vehicle.startEngine("car-key")) {
+          return vehicle.drive(60);
+        } else {
+          return "Engine failed to start.";
+        }
+      }
+      console.log(operateVehicle(myCar));
+    }
+  });
+  require_main();
+})();

05_typescript/uebungen/u03_vehicle-interface/src/main-christian.ts

@@ -0,0 +1,24 @@
+interface Vehicle {
+  startEngine: (key: string) => boolean;
+  drive: (speed: number) => string;
+}
+
+const myCar = {
+  startEngine: (key: string) => {
+    console.log(`Engine started with key: ${key}`);
+    return true;
+  },
+  drive: (speed: number) => {
+    return `Driving at ${speed} km/h`;
+  },
+};
+
+function operateVehicle(vehicle: Vehicle): string {
+  if (vehicle.startEngine('car-key')) {
+    return vehicle.drive(60);
+  } else {
+    return 'Engine failed to start.';
+  }
+}
+
+console.log(operateVehicle(myCar));

05_typescript/uebungen/u03_vehicle-interface/src/main.ts

@@ -1,24 +1,40 @@
-interface Vehicle {
-  startEngine: (key: string) => boolean;
-  drive: (speed: number) => string;
-}
-
-const myCar = {
-  startEngine: () => {
-    console.log('Engine started');
-    return true;
-  },
-  drive: () => {
-    return 'Driving at default speed';
-  },
-};
-
-function operateVehicle(vehicle: Vehicle): string {
-  if (vehicle.startEngine('car-key')) {
-    return vehicle.drive(60);
-  } else {
-    return 'Engine failed to start.';
+{
+  interface Vehicle {
+    startEngine: (key: string) => boolean;
+    drive: (speed: number) => string;
   }
-}
 
-console.log(operateVehicle(myCar));
+  const myCar = {
+    startEngine: (key: string) => {
+      let returnBoolean = false;
+
+      if (key === 'car-key') {
+        console.log('Engine started');
+        returnBoolean = true;
+      }
+
+      return returnBoolean;
+    },
+    drive: (speed: number) => {
+      let returnString = 'Driving at default speed';
+
+      if (speed < 60) {
+        returnString = "You're an old man and way too slow";
+      } else if (speed > 60) {
+        returnString = 'You are an racer! Careful, the police is already watching you!';
+      }
+
+      return returnString;
+    },
+  };
+
+  function operateVehicle(vehicle: Vehicle): string {
+    if (vehicle.startEngine('car-key')) {
+      return vehicle.drive(60);
+    } else {
+      return 'Engine failed to start.';
+    }
+  }
+
+  console.log(operateVehicle(myCar));
+}

05_typescript/unterricht/tag28/01_ts-fundamentals/assets/js/06b_optional-exception-js.js

@@ -24,5 +24,7 @@
 
   const weather = [{ main: [{ icon: '10dn', description: 'Clouds' }] }];
 
-  console.log(weather[0]?.test[0]?.test);
+  // seit 2020
+  console.log(weather[0].test); // undefined
+  console.log(weather[0]?.main?.[0]?.test); // undefined
 }

05_typescript/unterricht/tag28/01_ts-fundamentals/src/02_unions.ts

@@ -17,6 +17,7 @@
   function getResult(): string | number {
     return Math.random() > 0.5 ? 'Success' : 404;
   }
+
   function getResult2(): string {
     return Math.random() > 0.5 ? 'success' : 'error';
   }

05_typescript/unterricht/tag28/01_ts-fundamentals/src/06_optional-exception.ts

@@ -3,6 +3,7 @@
   interface Vehicle {
     make: string;
     model: string;
+    color?: string;
     startEngine: () => string;
     stopEngine?: () => string; // ?: optional Property
   }

05_typescript/unterricht/tag28/01_ts-fundamentals/src/06b_optional-exception-js.js

@@ -0,0 +1,30 @@
+// Optional Exception Parameter in JS
+{
+  const vehicle = {
+    make: 'Toyota',
+    model: 'Corolla',
+
+    startEngine: function () {
+      return `${this.make} engine startet`;
+    },
+
+    // Methode - Kurzschreibweise ES6
+    startEngine2() {
+      return `${this.make} engine startet`;
+    },
+
+    stopEngine: () => {
+      console.log(this); // => window (browser) | undefined (node)
+      return `${vehicle.make} engine gestoppt`;
+    },
+  };
+
+  console.log(vehicle.startEngine()); // => 'Toyota engine startet'
+  console.log(vehicle.stopEngine()); // => 'Toyota engine startet'
+
+  const weather = [{ main: [{ icon: '10dn', description: 'Clouds' }] }];
+
+  // seit 2020
+  console.log(weather[0].test); // undefined
+  console.log(weather[0]?.main?.[0]?.test); // undefined
+}