JavaScript Tutorial/Number Data Type/Integer
Содержание
- 1 Calculation on integers
- 2 Compare two numbers
- 3 Define and use integers
- 4 Generate random number
- 5 Integers
- 6 Integers can also be represented as either octal (base 8) or hexadecimal (base 16) literals.
- 7 To create a hexadecimal literal, the first digit must be a zero (0) followed by the letter x, followed by any number of hexadecimal digits (0-9 and A-F).
- 8 Using Binary Flags
Calculation on integers
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<html> <head> <title>A Simple Page</title> <script language="JavaScript">
</script> </head> <body> </body> </html></source>
Compare two numbers
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<HTML> <HEAD> </HEAD> <BODY> <SCRIPT language="JavaScript">
</SCRIPT> </BODY> </HTML></source>
Define and use integers
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<html> <head> <title>A Simple Page</title> <script language="JavaScript">
</script> </head> <body> </body> </html></source>
Generate random number
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<html> <head> <title>numberMaker</title> <script> var number; number = Math.random(); alert ("Here"s my number: " + number); </script> </head> <body>
Hit the Reload key to see a new number!
</body> </html></source>
Integers
Integers are numbers that contain no fractional parts.
Integers are numbers that can be positive or negative.
Integers are numbers that can be formatted as a decimal, octal, or hexadecimal in JavaScript.
Decimal integers is made up of numbers from 0 to 9 and cannot begin with leading zeros.
Octal integers, also referred to as base-8, must begin with a leading zero. Each digit following the leading zero can be 0 to 7.
Hexadecimal integers, also referred to as base-16, must begin with 0x or 0X. Each digit following the leading zero can be 0 through 15, but 10 through 15 are represented by the letters a (or A) through f (or F).
5. 3. Integer 5. 3. 1. Integers 5. 3. 2. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Integerscanalsoberepresentedaseitheroctalbase8orhexadecimalbase16literals.htm">Integers can also be represented as either octal (base 8) or hexadecimal (base 16) literals.</a> 5. 3. 3. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Tocreateahexadecimalliteralthefirstdigitmustbeazero0followedbytheletterxfollowedbyanynumberofhexadecimaldigits09andAF.htm">To create a hexadecimal literal, the first digit must be a zero (0) followed by the letter x, followed by any number of hexadecimal digits (0-9 and A-F).</a> 5. 3. 4. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Defineanduseintegers.htm">Define and use integers</a> 5. 3. 5. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Calculationonintegers.htm">Calculation on integers</a> 5. 3. 6. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Comparetwonumbers.htm">Compare two numbers</a> 5. 3. 7. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/Generaterandomnumber.htm">Generate random number</a> 5. 3. 8. <A href="/Tutorial/JavaScript/0100__Number-Data-Type/UsingBinaryFlags.htm">Using Binary Flags</a>
Integers can also be represented as either octal (base 8) or hexadecimal (base 16) literals.
For an octal literal, the first digit must be a zero (0).
The following digits can be any octal digit (0 through 7).
<source lang="javascript">
var iNum = 070;</source>
To create a hexadecimal literal, the first digit must be a zero (0) followed by the letter x, followed by any number of hexadecimal digits (0-9 and A-F).
The digits may be in uppercase or lowercase.
<source lang="javascript">
var iNum = 0x1f; var iNum2 = 0xAB;</source>
Using Binary Flags
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<html> <head> <title>Using Binary Flags</title> <script type="text/javascript"> var FIELD_A = 0x1; // 00001 var FIELD_B = 0x2; // 00010 var FIELD_C = 0x4; // 00100 var FIELD_D = 0x8; // 01000 var FIELD_E = 0x10; // 10000 var fieldsSet = FIELD_A | FIELD_C | FIELD_E; if ((fieldsSet & FIELD_A) && (fieldsSet & FIELD_C)) {
document.write("Fields A and C are set");
} </script> </head> </body> </html></source>
