string to number

#isNaN #typeof

parseInt() / parseFloat()
文字 轉換 數字

<pre><B>parseInt(string, radix) 字串轉成整數</B> string argument and returns an integer string : 待轉成數字的字串。 radix : 從 2 到 36，能代表該進位系統的數字。 parseInt( "10" ,10) = <script>document.write( parseInt("10") ) </script> parseInt("-13.00" ,10) = <script>document.write( parseInt("-13.00") ) </script> parseInt( "16.33" ,10) = <script>document.write( parseInt("16.33") ) </script> parseInt("34 45 6",10) = <script>document.write( parseInt("34 45 6") ) </script> parseInt("40years",10) = <script>document.write( parseInt("40 years") ) </script> parseInt( "He 40" ,10) = <script>document.write( parseInt("He 40") ) </script> parseInt( "15*3" ,10) = <script>document.write( parseInt( "15*3", 10) ) </script> parseInt( "15e2" ,10) = <script>document.write( parseInt( "15e2", 10) ) </script> parseInt( "42 " ,8) = <script>document.write( parseInt("42",8) ) </script> parseInt( "42" ,16) = <script>document.write( parseInt("42",16) ) </script> parseInt( "0xF" ,16) = <script>document.write( parseInt(" 0xF" , 16 ) ) </script> parseInt( "0xA" ,16) = <script>document.write( parseInt(" 0xA" , 16 ) ) </script> parseInt( "1111" ,2 ) = <script>document.write( parseInt(" 1111" , 2 ) ) </script> </pre> <style> B {text-align: center; font-size: 30px; font-weight: bold; text-shadow: 10px 6px 10px grey; color: blue; } pre {font-size: 20px;} ol {background-color:tan ;} li {background-color:ivory ;padding-left:10px;text-align: left;} li {word-break: break-word } r { color:red} </style>

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<pre><B>parseFloat(string) 字串轉成浮點數</B> string argument and returns a floating string : 待轉成數字的字串。 parseFloat( "10" ) = <script>document.write( parseFloat("10") ) </script> parseFloat( "10.233" ) = <script>document.write( parseFloat("10.233") ) </script> parseFloat("-10.233" ) = <script>document.write( parseFloat("-10.233") ) </script> parseFloat("34 45 66") = <script>document.write( parseFloat("34 45 66") ) </script> parseFloat( "0x6" ) = <script>document.write( parseFloat(" 0x6 ") ) </script> parseFloat("40 years") = <script>document.write( parseFloat("40 years") ) </script> parseFloat( "He 40" ) = <script>document.write( parseFloat("He 40") ) </script> </pre> <style> B {text-align: center; font-size: 30px; font-weight: bold; text-shadow: 10px 6px 10px grey; color: blue; } pre {font-size: 20px;} ol {background-color:tan ;} li {background-color:ivory ;padding-left:10px;text-align: left;} li {word-break: break-word } r { color:red} </style>

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<pre><B>String(value) 數字轉成字串</B> input number into a string value : 數字。 String( 10 ) = <script>document.write( String(10) ) </script> String( -10 ) = <script>document.write( String(-10) ) </script> String(10.23) = <script>document.write( String(10.23) ) </script> String(0xA) = <script>document.write( String(0xA) ) </script> String(0xff) = <script>document.write( String(0xff) ) </script> String(5+3) = <script>document.write( String(5+3) ) </script> String(5/3) = <script>document.write( String(5/3) ) </script> String(true) = <script>document.write( String(true) ) </script> String(false) = <script>document.write( String(false) ) </script> String(Boolean(0)) = <script>document.write( String(Boolean(0)) ) </script> String(Boolean(1)) = <script>document.write( String(Boolean(1)) ) </script> String([1,2,3,4]) = <script>document.write( String([1,2,3,4]) ) </script> String({"name":"12"}) = <script>document.write( String({"name":"12"}) ) </script> </pre> <style> B {text-align: center; font-size: 30px; font-weight: bold; text-shadow: 10px 6px 10px grey; color: blue; } pre {font-size: 20px;} ol {background-color:tan ;} li {background-color:ivory ;padding-left:10px;text-align: left;} li {word-break: break-word } r { color:red} </style>

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<pre><B>number.toString(radix) 數字作轉成字符串 </B> Convert numbers to strings number : 數字。 radix : 可選。使用的基數 , 2/8/16 進制。 ( 10).toString( ) = <script>document.write( (10).toString( ) ) </script> (-10).toString( ) = <script>document.write( (-10).toString( ) ) </script> (1.25).toString( ) = <script>document.write( (1.25).toString( ) ) </script> ( 15).toString( 2) = <script>document.write( (15).toString(2 ) ) </script> ( 15).toString( 8) = <script>document.write( (15).toString(8 ) ) </script> ( 15).toString(16) = <script>document.write( (15).toString(16 ) ) </script> (0xA).toString( ) = <script>document.write( (0xA).toString( ) ) </script> (0xF).toString( ) = <script>document.write( (0xF).toString( ) ) </script> (0xFF).toString( ) = <script>document.write( (0xFF).toString( ) ) </script> (5+3).toString( ) = <script>document.write( (5+3).toString( ) ) </script> (5/3).toString( ) = <script>document.write( (5/3).toString( ) ) </script> Boolean(0).toString( ) = <script>document.write( Boolean(0).toString( ) ) </script> Boolean(1).toString( ) = <script>document.write( Boolean(1).toString( ) ) </script> ([1,2,3]).toString( ) = <script>document.write( ([1,2,3]).toString( ) ) </script> ({"name":"12"}).toString( ) = <script>document.write( ({"name":"12"}).toString( ) ) </script> </pre> <style> B {text-align: center; font-size: 30px; font-weight: bold; text-shadow: 10px 6px 10px grey; color: blue; } pre {font-size: 20px;} ol {background-color:tan ;} li {background-color:ivory ;padding-left:10px;text-align: left;} li {word-break: break-word } r { color:red} </style>

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<pre><B>typeof 檢驗運算元的型別</B> typeof type operator typeof 37 = <script>document.write(typeof 37 ) </script> typeof 3.14 = <script>document.write( typeof 3.14 ) </script> typeof (6+6) = <script>document.write( typeof (6+6) ) </script> typeof Math.LN2 = <script>document.write( typeof Math.LN2 ) </script> typeof Infinity = <script>document.write( typeof Infinity ) </script> typeof "" = <script>document.write( typeof "" ) </script> typeof " " = <script>document.write( typeof " " ) </script> typeof "love" = <script>document.write( typeof "love" ) </script> typeof true = <script>document.write( typeof true ) </script> typeof false = <script>document.write( typeof false ) </script> typeof undefined = <script>document.write( typeof undefined ) </script> typeof html = <script>document.write( typeof html ) </script> typeof {a:1} = <script>document.write( typeof {a:1} ) </script> typeof [1, 2, 4] = <script>document.write( typeof [1, 2, 4] ) </script> typeof new Date = <script>document.write( typeof new Date ) </script> typeof {name:'john', age:34} = <script>document.write( typeof {name:'john', age:34} ) </script> typeof function(){} = <script>document.write( typeof function () {} ) </script> typeof Math.sin = <script>document.write( typeof Math.sin ) </script> </pre> <style> B {text-align: center; font-size: 30px; font-weight: bold; text-shadow: 10px 6px 10px grey; color: blue; } pre {font-size: 20px;} ol {background-color:tan ;} li {background-color:ivory ;padding-left:10px;text-align: left;} li {word-break: break-word } r { color:red} </style>

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#html #網頁格式 #style #div #string 文字數字轉換 parseInt() #string 文字數字轉換 parseFloat() #string 文字數字轉換 toString() #string 文字數字型別 typeof #string 文字數字型別 String() #parseInt() string argument and returns an integer #parseFloat() string argument and returns a floating #toString() Convert numbers to strings #typeof typeof type operator #String() input number into a string