JavaScript 类型转换(String、toString、toFixed、toPrecision、toExponential、Number、parseFloat、parseInt、Boolean) 1、转换字符(String、toString、toFixed、toPrecision、toExponential) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 varii=1234.456; varbb=false; //数字转换字符 docum...
The string to be parsed and converted to a number. Returns The parsed number, orNaNifsdoes not begin with a valid number. In JavaScript 1.0,parseFloat( )returns 0 instead ofNaNwhenscannot be parsed as a number. Description parseFloat( )parses and returns the first number that occurs ins....
parseFloat() 函数可解析一个字符串,并返回一个浮点数。该函数指定字符串中的首个字符是否是数字。如果是,则对字符串进行解析,直到到达数字的末端为止,然后以数字返回该数字,而不是作为字符串。语法parseFloat(string)参数描述 string 必需。要被解析的字符串。
console.log(parseFloat(null)); //NaN console.log(parseInt(10.1)); //10 1. 2. 3. 4. 2.String 情景1:String(val)或者val.toString() 转换规则:除对象以外,都是直接用字符串包起来 console.log(String(1)); //'1' console.log(String(NaN)); //'NaN' console.log(String(null)); //'null'...
有区别，小写的是primitive，大写的是object。大写的那几个类型的存在是一个错误。不要用大写的。
number -> string: 数字转化成16进制的字符串 var m = 122; var n = m.toString(16); console.log(n); python中进制转换逻辑 // 2.parseFloat 强制转换成浮点型/* 要求: 必须数字开头; */var num = 100; //100var num = "abc"; //NaNvar num = "123"; //123var num = "123abc"; //123...
let number = parseFloat(inputString);// number will be 100 处理空白、字符和特殊情况 空白:忽略前导空格 字符继续解析,直到函数解析到一个无法转换成数字的字符。如果是第一个字符,函数将返回 NaN 特殊情况:没有 redix 参数。 3. + 运算符 这是一种在 javascript 中将字符串转换为数字的速记方法 ...
This JavaScript tutorial explains how to use the Number method called parseFloat() with syntax and examples. In JavaScript, parseFloat() is a Number method that is used to parse a string and return its value as a floating point number.
Converting a string to a number in JavaScript issurprisingly subtle. WithNaN,implicit radixes, and numbers vsNumbers, there are a lot of ways to shoot yourself in the foot. In this article, I'll cover the tradeoffs ofparseFloat()vsNumber()andNumber.isNaN()vsisNaN(). I'll also describe...
parseInt()also can convert hexadecimal values and values with the different base number systems, like the binary system, the octal system, etc. For more information, check outthe docs. Similarly, we can useparseFloat()to convert a string to a floating-point number. ...