Skip to content

Commit 72c43ff

Browse files
coderzamancoderzaman
committed
Condition(Control Flow)
1 parent 57ac5da commit 72c43ff

File tree

2 files changed

+274
-0
lines changed

2 files changed

+274
-0
lines changed

‎07. Condition(Control Flow)/index.html

Lines changed: 14 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,14 @@
1+
<!DOCTYPE html>
2+
<html lang="en">
3+
<head>
4+
<meta charset="UTF-8">
5+
<meta name="viewport" content="width=device-width, initial-scale=1.0">
6+
<title>Document</title>
7+
</head>
8+
<body>
9+
<h1 id="showMessage"></h1>
10+
<!-- link javacript file -->
11+
<script src="js/script.js"></script>
12+
13+
</body>
14+
</html>

‎07. Condition(Control Flow)/js/script.js

Lines changed: 260 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,260 @@
1+
// Controlflow
2+
3+
// Conditional Statements
4+
// In JavaScript we have the following conditional statements:
5+
// Very often when you write code, you want to perform different actions for different decisions.
6+
// You can use conditional statements in your code to do this.
7+
8+
9+
// Use if to specify a block of code to be executed, if a specified condition is true
10+
// Use else to specify a block of code to be executed, if the same condition is false
11+
// Use else if to specify a new condition to test, if the first condition is false
12+
// Use switch to specify many alternative blocks of code to be executed
13+
14+
15+
// The if Statement
16+
// Use the if statement to specify a block of JavaScript code to be executed if a condition is true.
17+
18+
// Syntax
19+
// if (condition) {
20+
// // block of code to be executed if the condition is true
21+
// }
22+
23+
let hour = 2;
24+
if (hour < 18) {
25+
var greeting = "Good day";
26+
}
27+
28+
console.log(greeting);
29+
30+
// The else Statement
31+
// Use the else statement to specify a block of code to be executed if the condition is false.
32+
33+
// Syntax
34+
// if (condition) {
35+
// // block of code to be executed if the condition is true
36+
// } else {
37+
// // block of code to be executed if the condition is false
38+
// }
39+
hour = 20;
40+
if (hour < 18) {
41+
greeting = "Good day";
42+
} else {
43+
greeting = "Good evening";
44+
}
45+
46+
console.log(greeting);
47+
48+
49+
// The else if Statement
50+
// Use the else if statement to specify a new condition if the first condition is false.
51+
52+
// Syntax
53+
// if (condition1) {
54+
// // block of code to be executed if condition1 is true
55+
// } else if (condition2) {
56+
// // block of code to be executed if the condition1 is false and condition2 is true
57+
// } else {
58+
// // block of code to be executed if the condition1 is false and condition2 is false
59+
// }
60+
let time = 9;
61+
if (time < 10) {
62+
greeting = "Good morning";
63+
} else if (time < 20) {
64+
greeting = "Good day";
65+
} else {
66+
greeting = "Good evening";
67+
}
68+
69+
console.log(greeting);
70+
71+
72+
// if there is oneline in any conditional blokc we can skip {}
73+
74+
if (time < 10) greeting = "Good morning";
75+
else if (time < 20) greeting = "Good day";
76+
else greeting = "Good evening";
77+
78+
79+
console.log(greeting);
80+
81+
//If there is more than one line in any conditional blokc we must be write code with in {}
82+
83+
if (time < 10) {
84+
greeting = "Good morning";
85+
console.log("Have a great day");
86+
} else if (time < 20) {
87+
greeting = "Good day";
88+
console.log("Have a great day");
89+
} else {
90+
greeting = "Good evening";
91+
console.log("Have a great day");
92+
}
93+
94+
console.log(greeting);
95+
96+
97+
// Excercise:
98+
// Find largest number form 3
99+
let num1 = parseInt(prompt("Enter Number 1: "));
100+
let num2 = parseInt(prompt("Enter Number 2: "));
101+
let num3 = parseInt(prompt("Enter Number 3: "));
102+
103+
if (num1 >= num2 && num1 >= num3) {
104+
console.log(`${num1} is grater than ${num2}, ${num3}`);
105+
} else if (num2 >= num3) {
106+
console.log(`${num2} is grater than ${num1}, ${num3}`);
107+
} else {
108+
console.log(`${num3} is grater than ${num1}, ${num2}`);
109+
}
110+
111+
//Nested if
112+
if (num1 >= num2) {
113+
if (num1 >= num3) {
114+
console.log(`${num1} is grater than ${num2}, ${num3}`);
115+
} else {
116+
console.log(`${num3} is grater than ${num1}, ${num2}`);
117+
}
118+
} else if (num2 >= num3) {
119+
console.log(`${num2} is grater than ${num1}, ${num3}`);
120+
} else {
121+
console.log(`${num3} is grater than ${num1}, ${num2}`);
122+
}
123+
124+
// The JavaScript Switch Statement
125+
// Use the switch statement to select one of many code blocks to be executed.
126+
127+
// Syntax
128+
// switch(expression) {
129+
// case x:
130+
// // code block
131+
// break;
132+
// case y:
133+
// // code block
134+
// break;
135+
// default:
136+
// // code block
137+
// }
138+
139+
// This is how it works:
140+
// The switch expression is evaluated once.
141+
// The value of the expression is compared with the values of each case.
142+
// If there is a match, the associated block of code is executed.
143+
// If there is no match, the default code block is executed.
144+
145+
let currentMonth;
146+
switch(new Date().getMonth()){
147+
case 0:
148+
currentMonth = "January";
149+
break;
150+
case 1:
151+
currentMonth = "February";
152+
break;
153+
case 2:
154+
currentMonth = "March";
155+
break;
156+
case 3:
157+
currentMonth = "April";
158+
break;
159+
case 4:
160+
currentMonth = "May";
161+
break;
162+
case 5:
163+
currentMonth = "June";
164+
break;
165+
case 6:
166+
currentMonth = "July";
167+
break;
168+
case 7:
169+
currentMonth = "August";
170+
break;
171+
case 8:
172+
currentMonth = "September";
173+
break;
174+
case 9:
175+
currentMonth = "Octobor";
176+
break;
177+
case 10:
178+
currentMonth = "November";
179+
break;
180+
case 11:
181+
currentMonth = "December";
182+
break;
183+
default:
184+
currentMonth = "Something is wrong";
185+
break;
186+
187+
}
188+
189+
console.log(currentMonth);
190+
191+
// excercise:
192+
let score = parseFloat(prompt("Enter your score: "));
193+
194+
195+
if(score < 0 || 100 < score){
196+
console.log("Invalid score Input.");
197+
}else if(score < 40){
198+
console.log("Your Grade is F.");
199+
}else if(score < 45){
200+
console.log("Your Grade is D");
201+
}else if(score < 50){
202+
console.log("Your Grade is C");
203+
}else if(score < 55){
204+
console.log("Your Grade is C+");
205+
}else if(score < 60){
206+
console.log("Your Grade is B-");
207+
}else if(score < 65){
208+
console.log("Your Grade is B");
209+
}else if(score < 70){
210+
console.log("Your Grade is B+");
211+
}else if(score < 75){
212+
console.log("Your Grade is A-");
213+
}else if(score < 80){
214+
console.log("Your Grade is A");
215+
}else{
216+
console.log("Your Grade is A+");
217+
}
218+
219+
220+
// excercise
221+
222+
num1 = parseFloat(prompt("Plese Enter Number 1: "));
223+
num2 = parseFloat(prompt("Plese Enter Number 2: "));
224+
225+
let option = parseInt(prompt(`Enter the Option:
226+
1. Add
227+
2. Subtract
228+
3. Multiply
229+
4. Division`));
230+
231+
232+
let res = null;
233+
if(!isNaN(num1) && !isNaN(num2) && !isNaN(option)){
234+
switch(option){
235+
case 1:
236+
res = num1 + num2;
237+
break;
238+
case 2:
239+
res = num1 - num2;
240+
break;
241+
case 3:
242+
res = num1 * num2;
243+
break;
244+
case 4:
245+
res = num1 / num2;
246+
break;
247+
default:
248+
res = "Invalid Option";
249+
break;
250+
}
251+
}else{
252+
console.log("Invalid Input");
253+
}
254+
255+
if(res == null) console.log("No Result")
256+
else console.log("Result is: ", res);
257+
258+
259+
260+

0 commit comments

Comments
 (0)