javascript Object methods
toString([radix])
/* prevede objekt na string */
toLocaleString()
var myDate = new Date();
document.write( myDate.toLocaleString());
// 24. února 2009 10:50:02
valueOf()
var number = new Number();
number = Number(100);
if (!isNaN(number))
document.write(number.valueOf()); // 100
hasOwnProperty(proName)
var theObj = { prom : 'bla' };
if ( theObj.hasOwnProperty )
{
document.write( "Has 'prom': " + theObj.hasOwnProperty( 'prom' ) + 'n' ); // true
document.write( "Has 'prom2': " + theObj.hasOwnProperty( 'prom2' ) + 'n' ); // false
}
isPrototypeOf(object2)
function fc(){
var reg = new RegExp();
return (RegExp.prototype.isPrototypeOf(reg)); // return true.
}
propertyIsEnumerable(proName)
var a = new Array("apple", "banana", "cactus");
document.write(a.propertyIsEnumerable(2)); // true
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Další témata ....(Topics)
Multi-byte UNICODE PHP.
Pokud pracujete s diakritikou budou se Vám hodit funkce, které začínají mb_ tedy multi-byte funkce.Abyste nemuseli do každé funkce udávat kódování viz příklad
$mbLen = mb_strlen('žluťoučký','utf-8');
přidávejte na začátek kódu internal encoding
mb_internal_encoding('utf-8');
$mbLen = mb_strlen('žluťoučký');
Příklad si vyzkoušejte a ověřte hodnoty $mbLenHow to sort array in javascript.
sort diacritical diakritika
function sortCZ(a, b) {
var token = {'á': 'a', 'č': 'c', 'ď': 'd', 'é': 'e', 'ě': 'e', 'í': 'i', 'ň': 'n', 'ř': 'r', 'š': 's', 'ť': 't', 'ú': 'u', 'ů': 'u', 'ý': 'y', 'ž': 'z'};
var code_a = (token[a]) ? token[a].charCodeAt(0) + 0.5 : a.charCodeAt(0);
var code_b = (token[b]) ? token[b].charCodeAt(0) + 0.5 : b.charCodeAt(0);
// example s=115 š will 115.5 in array immediately after s OK :)
if(token[a]){
some = token[a].charCodeAt(0) + 0.5; // 115.5
some = token[a].charCodeAt(0); // 115
}
return code_a - code_b;
}
var ar = new Array("x","č","a","c","h","z","a","ř","e","ž","ě","ň","í","d","š");
ar.sort(sortCZ);
Udaje o prohlížeči
alert(navigator.appName); // Netscape
alert(navigator.appVersion); // 5.0(Windows; en-US)
alert(navigator.appCodeName); // Mozilla
alert(navigator.appMinorVersion); // subverze prohlížeče
alert(navigator.browserLanguage);
alert(navigator.cookieEnabled); // true - false
alert(navigator.cpuClass);
alert(navigator.onLine); // true když je připojen k síti
alert(navigator.platform);
alert(navigator.systemLanguage);
alert(navigator.userAgent);
alert(navigator.userLanguage);
// zjisteni detekce prohlizece Google Chrome
var bool_is_chrome = navigator.userAgent.toLowerCase().indexOf('chrome') > -1;
Tthis code works in all previous versions of browsers
Pause code by alert
Set timeout
Pause code by alert
var n = 1;
alert(n);
n = 5;
alert(n);
Set timeout
var n = 5;
// wait 5 second / do next code
// next code put into function and call this function by setTimeout
setTimeout("nextCodeFc (n)",5000); // wait for 5000 millisecond == 5 second and execute
// how put string as parameter into setTimeout
var str = "Hello string parameter!";
setTimeout('nextCodeFc("str")',3000); // produce "str"
setTimeout('nextCodeFc("'+str+'")',3000); // produce "Hello string parameter!"
setTimeout("nextCodeFc(str)",3000); // produce Hello string parameter!
function nextCodeFc (n){
// do work .........
alert(n);
}
// multiline string old school tip trick
// create elemnt div style none or hidden with text
var sMulitilineString = document.getElementById('idHiddenDiv').innerHTML; // get text from hidden div
// ES6 with quotes
const htmlString = 'Say hello to
multi-line
strings!';
(typeof "813") // string
(typeof 813) // number
parseInt("10.33") // returns 10 string to integer
parseInt('2def8'); // 2
parseInt('a2def8'); // NaN
parseFloat("10.33") // returns 10.33 string to float
var test_1 = 'string';
var test_2 = ' example';
var suma = test_1 + test_2;
var length = suma.length; // 14
var le = test_1.length; // 6
charAt(index)
/* Returns the character at the specified index */
var str = new String('Sample');
str.charAt(3)); // p
// startsWith
var str = "HELLO WORLD";
var res = str.charAt(0); // H
// endsWith
var res = str.charAt(str.length - 1); // D
charCodeAt(index)
/* Returns an integer representing the Unicode encoding
of the character at the specified location */
var str = new String('Sample');
str.charCodeAt(3)); // 112
fromCharCode([code1[, code2[, ...[, codeN]]]])
/* Returns a string from a number of Unicode character values */
var e = window.event;
var str = String.fromCharCode(e.keyCode); // keydown etc.
concat([item1[, item2[, . . . [, itemN]]]])
/* Returns a new array consisting of a combination of two or more arrays */
var arr1 = new Array("Hello, ", "Dolly uranove");
var arr2 = new Array("World!", "dort");
var myConcatArray = arr1.concat(arr2);
alert(myConcatArray[3]); // dort
concat([string2[, string3[, . . . [, stringN]]]])
/* Returns a string value containing the concatenation
of two or more supplied strings */
var string1 = new String("Hello, ");
var string2 = new String("World!");
var myConcatString = string1.concat(string2); // Hello, World!
indexOf(subString[, startIndex])
/* Returns the character position where the first occurrence
of a substring occurs within a String object */
lastIndexOf(substring[, startindex])
/* Returns the last occurrence of a substring within a String object */
localeCompare(stringExp)
/* Returns a value indicating whether two strings
are equivalent in the current locale */
var str1 = "1";
var str2 = "2";
var n = str1.localeCompare(str2); // -1
var str1 = "2";
var str2 = "2";
var n = str1.localeCompare(str2); // 0
var str1 = "a";
var str2 = "b";
var n = str1.localeCompare(str2); // -1
var str1 = "b";
var str2 = "a";
var n = str1.localeCompare(str2); // 1
match(rgExp)
/* Executes a search on a string using a regular expression
pattern, and returns an array containing the results of that search */
var rgExp = /some text/g;
replace(rgExp, replaceText)
/* Returns a copy of a string with text replaced
using a regular expression or search string */
search(rgExp)
/* Returns the position of the first substring
match in a regular expression search */
n // A newline character
. // Any character except a newline
r // A carriage return character
t // A tab character
b // A word boundary (the start or end of a word)
B // Anything but a word boundary
d // Any digit (same as [0-9])
D // Anything but a digit (same as [^0-9])
s // Single whitespace (space, tab, newline, etc.)
S // Single nonwhitespace
w // A "word character” (same as [A-Za-z0-9_])
W // A "nonword character” (same as [^A-Za-z0-9_])
slice(start, [end])
/* Returns a section of an array or string */
var myString = new String("This is a test");
var mySlice = myString.slice(2,6); // is i // pos: 2 to 5 // 0==T, 1==h, 2==i, 3==s, 4==" ", 5==i
mySlice = myString.slice(-3); // est // end of string
mySlice = myString.slice(0); // This is a test
split([separator[, limit]])
/* Returns the array of strings that results
when a string is separated into substrings */
var str = "one two three";
var words = str.split(" ");
var len = words.length; // 3
substring(start, end)
/* Returns the substring at the specified location
within a String object */
var inpTxt = "Hello there";
alert(inpTxt.substring(6, 10)); // ther
substr(start [, length ])
// Returns a substring beginning at a specified
// location and having a specified length
var s = "The love in Spain.";
ss = s.substr(12, 5); // Spain
tolocaleLowerCase()
/* Returns a string where all alphabetic characters
have been converted to lowercase, taking into account
the host environment's current locale */
toUpperCase()
/* Returns a string where all alphabetic characters
have been converted to uppercase */
var myString = "My text";
myString.anchor //places an HTML anchor with a NAME attribute around specified text in the object
myString.big
myString.blink
myString.bold
myString.concat
myString.fixed
myString.fontcolor
myString.fontsize
myString.charAt
myString.charCodeAt
myString.indexOf
myString.italics
myString.lastindexOf
myString.length
myString.link
myString.match
myString.replace
myString.search
myString.slice
myString.small
myString.split
myString.strike
myString.sub //places HTML SUB tags around text in a String object
myString.substr
myString.substring
myString.sup
myString.toLowerCase
myString.toString
myString.toUpperCase
myString.valueOf
var str = "58";
var res = str.valueOf();
var type = (typeof res); // string
var str = 58;
var res = str.valueOf();
var type = (typeof res); // number
Editace: 18 10 2016
Počet článků v kategorii: 77
Url:javascript-object-methods