Functions added

08-Function/01-intro/intro.go

@@ -0,0 +1,24 @@
+package main
+
+func main() {
+	Print1()
+	str := Print2()
+	println(str)
+	str3 := Print3("33")
+	println(str3)
+}
+
+// without input and output
+func Print1() {
+	println("Hello World1")
+}
+
+// without input and with output
+func Print2() string {
+	return "Hello World2"
+}
+
+// with input and output
+func Print3(str string) string {
+	return "Hello World " + str
+}

08-Function/02-MultipleReturns/example.go

@@ -0,0 +1,28 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	order1, tax1 := CalculateRoomPrice("standard", 3, 2)
+
+	fmt.Printf("order1 price: %d, tax1: %f\n", order1, tax1)
+
+}
+
+func CalculateRoomPrice(roomType string, nights int, personCount int) (int, float64) {
+	var price int
+	var tax float64
+
+	switch roomType {
+	case "standard":
+		price = nights * 140000 * personCount
+	case "double":
+		price = nights * 220000 * personCount
+	case "suite":
+		price = nights * 350000 * personCount
+	}
+
+	tax = float64(price) * 0.09
+	return price, tax
+}

08-Function/03-NamedReturnValue/example.go

@@ -0,0 +1,28 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	price, finalPrice, tax := CalculateRoomPrice("standard", 3, 2)
+
+	fmt.Printf("order price: %d, tax: %f\n finalPrice = price + tax (%d + %f) => %d\n", price, tax, price, tax, finalPrice)
+
+}
+
+func CalculateRoomPrice(roomType string, nights int, personCount int) (price int, finalPrice int, tax float64) {
+
+	switch roomType {
+	case "standard":
+		price = nights * 140000 * personCount
+	case "double":
+		price = nights * 220000 * personCount
+	case "suite":
+		price = nights * 350000 * personCount
+	}
+
+	tax = float64(price) * 0.09
+	finalPrice = price + int(tax)
+
+	return
+}

08-Function/04-Variadic/example.go

@@ -0,0 +1,19 @@
+package main
+
+import "reflect"
+
+func main() {
+	Calculator(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, "Ali")
+}
+
+func Calculator(numbers ...interface{}) {
+	for _, item := range numbers {
+
+		switch item.(type) {
+		case int:
+			println("int:", reflect.ValueOf(item).Int())
+		case string:
+			println("string:", reflect.ValueOf(item).String())
+		}
+	}
+}

08-Function/04-Variadic/example1.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	sum, multiply := Calculator("Ali", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+
+	fmt.Printf("sum: %d, multiply: %d\n", sum, multiply)
+}
+
+func Calculator(name string, numbers ...int) (sum int, mul int) {
+	mul = 1
+	for _, number := range numbers {
+		sum += number
+		mul *= number
+	}
+	return
+}

08-Function/04-Variadic/example2.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	PrintLog("Ali", 1, "Reza", 3, "Error", 5, 6, "Info", 8, 9, false)
+
+}
+
+func PrintLog(logs ...interface{}) {
+	for i, item := range logs {
+		fmt.Printf("%d: %v\n", i, item)
+	}
+}

08-Function/05-Anonymous/example1.go

@@ -0,0 +1,43 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	myFunc := func() {
+		fmt.Println("Hello World")
+	}
+
+	x := 1200
+
+	myFunc()
+	myFunc()
+
+	println(func(numbers ...int) int {
+		var total int
+		for _, number := range numbers {
+			total += number
+			x++
+			println(&x)
+		}
+		return total
+	}(1, 2, 3, 4, 5))
+
+	println(x)
+
+	sum := func(numbers ...int) int {
+		var total int
+		for _, number := range numbers {
+			total += number
+			x++
+			println(&x)
+		}
+		return total
+	}
+
+	println(sum(1, 2, 3, 4, 5))
+	println(x)
+	println(sum(1, 2, 3, 4, 5, 6, 7, 8, 9, 10))
+	println(x)
+
+}

08-Function/05-Anonymous/example2.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+)
+
+func main() {
+
+	numbers := []int{12, 5, 48, 32, 1, 2, 74, 36, 90, 100, 95, 42}
+
+	fmt.Printf("%v\n", numbers)
+
+	sortingFunc := func(i, j int) bool {
+		return numbers[i] < numbers[j]
+	}
+	sort.Slice(numbers, sortingFunc)
+
+	fmt.Printf("%v\n", numbers)
+}

08-Function/06-Clouser/example.go

@@ -0,0 +1,37 @@
+package main
+
+import "time"
+
+func main() {
+	firstName := "Ali"
+	names := []string{"Ali", "Reza", "Peyman", "Pejman", "Pejman1", "Pejman2", "Pejman3", "Pejman4"}
+
+	printFirstNameFunc := func() {
+		println(firstName)
+	}
+
+	firstName = "Reza"
+
+	printFirstNameFunc()
+
+	//---------------------------------------
+
+	for i, name := range names {
+		go func() {
+			name = "*" + name
+			println(i, name)
+		}()
+	}
+
+	time.Sleep(time.Second * 1)
+
+	for i, item := range names {
+		go func(index int, name string) {
+			name = "*" + name
+			println(index, name)
+		}(i, item)
+	}
+
+	time.Sleep(time.Second * 1)
+
+}

08-Function/07-Defer/destination.txt

@@ -0,0 +1 @@
+this is test

08-Function/07-Defer/example.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"io"
+	"os"
+)
+
+func main() {
+
+	defer println("Bye")
+	defer println("Good")
+
+	for i := 0; i < 10; i++ {
+		defer println(i)
+	}
+
+	println("Hello")
+
+	CopyFile("F:\\GolangTutorial\\08-Function\\07-Defer\\destination.txt", "F:\\GolangTutorial\\08-Function\\07-Defer\\source.txt")
+
+}
+
+func CopyFile(destinationName, sourceName string) (written int64, err error) {
+
+	source, err := os.Open(sourceName)
+
+	if err != nil {
+		return
+	}
+
+	defer source.Close()
+
+	destination, err := os.Create(destinationName)
+
+	if err != nil {
+		return
+	}
+
+	defer destination.Close()
+
+	return io.Copy(destination, source)
+
+}

08-Function/07-Defer/source.txt

@@ -0,0 +1 @@
+this is test