علاقه مندان به جاوا اسکریپت

saalek110

saalek110

Well-Known Member
چاپ روی دکمه


JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript HTML Events</h2>
<button onclick="this.innerHTML=Date()">The time is?</button>

</body>
</html>

تاریخ روی دکمه چاپ میشه
 
saalek110

saalek110

Well-Known Member
رویدادها :
ما با رویداد کلیک در کدهای پستهای قبلی کار کردیم حالا با رویدادهای دیگری آشنا می شویم:
EventDescription
onchangeAn HTML element has been changed
onclickThe user clicks an HTML element
onmouseoverThe user moves the mouse over an HTML element
onmouseoutThe user moves the mouse away from an HTML element
onkeydownThe user pushes a keyboard key
onloadThe browser has finished loading the page
 
saalek110

saalek110

Well-Known Member
می رویم سراغ رشته ها
رشته عبارتی کاراکتری است ، یک متغیررشته ای تعریف می کنیم مثلا برای نام

طول رشته

JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript Strings</h1>
<h2>The length Property</h2>

<p>The length of the string is:</p>
<p id="demo"></p>

<script>
let text = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
document.getElementById("demo").innerHTML = text.length;
</script>

</body>
</html>

طول رشته ساخته شده را اندازه گرفته


www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com
 
saalek110

saalek110

Well-Known Member
JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Strings</h2>

<p>The escape sequence \" inserts a double quote in a string.</p>

<p id="demo"></p>

<script>
let text = "We are the so-called \"Vikings\" from the north.";
document.getElementById("demo").innerHTML = text;
</script>

</body>
</html>



www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com


خواسته داخل رشته دابل کوتیشن به کار ببره ، از بک اسلش استفاده کرده تا دابل کوتو به عنوان بستن رشته تعبیر نشه.
 
saalek110

saalek110

Well-Known Member
JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Strings</h2>

<p>The escape sequence \' inserts a single quote in a string.</p>

<p id="demo"></p>

<script>
let text = 'It\'s alright.';
document.getElementById("demo").innerHTML = text;
</script>

</body>
</html>

این هم مشابه پست قبلی ، این بار خواسته کوتیشن داخل رشته استفاده کنه

www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com



دیگه کد سوم را نقل نمی کنم ، در کد سوم خواسته از بک اسل اخل رشته استفاده بکنه باز جلویش بک اسلش گذاشته تا خنثی بشه.
 
saalek110

saalek110

Well-Known Member
Six other escape sequences are valid in JavaScript:

CodeResult
\bBackspace
\fForm Feed
\nNew Line
\rCarriage Return
\tHorizontal Tabulator
\vVertical Tabulator
 
saalek110

saalek110

Well-Known Member
توابع رشته ای


www.w3schools.com

W3Schools.com

W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more.
www.w3schools.com www.w3schools.com


String length
String slice()
String substring()
String substr()
String replace()
String replaceAll()
String toUpperCase()
String toLowerCase()
String concat()		String trim()
String trimStart()
String trimEnd()
String padStart()
String padEnd()
String charAt()
String charCodeAt()
String split()
 
saalek110

saalek110

Well-Known Member
توابع رشته ای را می گذارم برای بعد. فعلا مباحث بعدی را می رویم جلو.
 
saalek110

saalek110

Well-Known Member
توابع عددی

MethodDescription
toString()Returns a number as a string
toExponential()Returns a number written in exponential notation
toFixed()Returns a number written with a number of decimals
toPrecision()Returns a number written with a specified length
ValueOf()Returns a number as a number
 
saalek110

saalek110

Well-Known Member
JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Number Methods</h2>

<p>The toString() method converts a number to a string.</p>

<p id="demo"></p>

<script>
let x = 123;
document.getElementById("demo").innerHTML =
  x.toString() + "<br>" +
   (123).toString() + "<br>" +
   (100 + 23).toString();
</script>

</body>
</html>


www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com

عدد به رشته تبدیل شده
 
saalek110

saalek110

Well-Known Member
تعداد رقم اعشار

JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Number Methods</h2>

<p>The toPrecision() method returns a string, with a number written with a specified length:</p>

<p id="demo"></p>

<script>
let x = 9.656;
document.getElementById("demo").innerHTML =
  x.toPrecision() + "<br>" +
  x.toPrecision(2) + "<br>" +
  x.toPrecision(4) + "<br>" +
  x.toPrecision(6);
</script>

</body>
</html>

www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com
 
آخرین ویرایش:
saalek110

saalek110

Well-Known Member
MethodDescription
Number()Returns a number converted from its argument.
parseFloat()Parses its argument and returns a floating point number
parseInt()Parses its argument and returns a whole number
 
saalek110

saalek110

Well-Known Member
تابع number

JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Global Methods</h2>

<p>The Number() method converts variables to numbers:</p>

<p id="demo"></p>

<script>
document.getElementById("demo").innerHTML =
  Number(true) + "<br>" +
  Number(false) + "<br>" +
  Number("10") + "<br>" +
  Number("  10") + "<br>" +
  Number("10  ") + "<br>" +
  Number(" 10  ") + "<br>" +
  Number("10.33") + "<br>" +
  Number("10,33") + "<br>" +
  Number("10 33") + "<br>" +
  Number("John");
</script>

</body>
</html>

www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com
 
saalek110

saalek110

Well-Known Member
تابع parseInt


JavaScript: 
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript Global Functions</h2>
<h2>parseInt()</h2>
<p>The global JavaScript function parseInt() converts strings to numbers:</p>

<p id="demo"></p>

<script>
document.getElementById("demo").innerHTML =
  parseInt("-10") + "<br>" +
  parseInt("-10.33") + "<br>" +
  parseInt("10") + "<br>" +
  parseInt("10.33") + "<br>" +
  parseInt("10 6") + "<br>" +
  parseInt("10 years") + "<br>" +
  parseInt("years 10");
</script>

</body>
</html>

JavaScript Global Functions​

parseInt()​

The global JavaScript function parseInt() converts strings to numbers:

-10
-10
10
10
10
10
NaN


www.w3schools.com

W3Schools online HTML editor

The W3Schools online code editor allows you to edit code and view the result in your browser
www.w3schools.com www.w3schools.com
 
saalek110

saalek110

Well-Known Member
MethodDescription
Number.isInteger()Returns true if the argument is an integer
Number.isSafeInteger()Returns true if the argument is a safe integer
Number.parseFloat()Converts a string to a number
Number.parseInt()Converts a string to a whole number


 
saalek110

saalek110

Well-Known Member
www.w3schools.com

W3Schools.com

W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more.
www.w3schools.com www.w3schools.com
 
saalek110

saalek110

Well-Known Member
PropertyDescription
EPSILONThe difference between 1 and the smallest number > 1.
MAX_VALUEThe largest number possible in JavaScript
MIN_VALUEThe smallest number possible in JavaScript
MAX_SAFE_INTEGERThe maximum safe integer (253 - 1)
MIN_SAFE_INTEGERThe minimum safe integer -(253 - 1)
POSITIVE_INFINITYInfinity (returned on overflow)
NEGATIVE_INFINITYNegative infinity (returned on overflow)
NaNA "Not-a-Number" value
 
saalek110

saalek110

Well-Known Member
www.w3schools.com

W3Schools.com

W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more.
www.w3schools.com www.w3schools.com

سالک: اینکه این قسمتهارا توضیح نمی دهم برای اینه که اینها برای شروع کار لازم نیست و تخصصی است. ولی عناوین و لینکش را می گذارم برای کسی که نیاز داره.
 
آخرین ویرایش:
saalek110

saalek110

Well-Known Member
www.w3schools.com

W3Schools.com

W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more.
www.w3schools.com www.w3schools.com

بخش ارایه را هم نمی خواهم فعلا واردش بشم. چون برای شروع کار نیاز به آرایه نداریم.
 
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