NaN是Not a Number的缩写,表示一种特殊的浮点数,它与任何数值都不相等,包括自己。isNaN(NaN) // true isNaN(Infinity) // false isNaN(-Infinity) // false isNaN("hello") // true isNaN(true) // false NaN == NaN; false 在比较两个NaN值时,它们并不严格相等,而是被视为相等(因为JavaScript中...
代码语言:javascript 代码运行次数:0 运行 AI代码解释 publicenumUnicodeCategory{UppercaseLetter,LowercaseLetter,TitlecaseLetter,ModifierLetter,OtherLetter,NonSpacingMark,SpacingCombiningMark,EnclosingMark,DecimalDigitNumber,LetterNumber,OtherNumber,SpaceSeparator,LineSeparator,ParagraphSeparator,Control,Format,Surrogate,Pri...
In this example, the function returns true if the string contains any white space in it else it returns false Conclusion: So to detect any white space in a given string in Javascript we can use the regex test() method or the stringindexOf() method. Related Topics: How to check if Str...
1/**2* 判断一个字符串是否包含另一个字符串3* @param target4* @param it5* @returns {boolean}6*/7functioncontains(target,it) {8returntarget.indexOf(it) !== -1;9}1011/**12* 判定目标字符串是否位于原字符串的开始之处13* @param target14* @param str15* @param ignoreCase 是否忽略大小写...
...返回值类型:String 结果: (八)Contains方法 判断字符串是否包含指定的字符序列 返回值类型:Boolean 结果: 13410 String 的 intern() 方法解析 一、概述 JDK7 之前和之后的版本,String 的 intern() 方法在实现上存在差异,本文的说明环境是 JDK8,会在文末说明 intern() 方法的版本差异性。...intern() ...
functionemployee(id:number,name:string){this.id=idthis.name=name}varemp=newemployee(123,"admin")employee.prototype.email="admin@runoob.com"// 添加属性 emailconsole.log("员工号: "+emp.id)console.log("员工姓名: "+emp.name)console.log("员工邮箱: "+emp.email) ...
To check for case insensitive string contains, use the regular expressions. Add suffix “i” after the string regular expression as shown. var actualstring = "Javascript Regular Exp"; var regexp = "javascript"; /regexp/i.test(actualstring); //returns true ...
下面重点解释第四种先看看注释When the intern method is invoked, if the pool already contains a ...
A boolean.trueif the string contains the value, otherwisefalse. More Examples Start at position 12: lettext ="Hello world, welcome to the universe."; letresult = text.includes("world",12); Try it Yourself » Related Pages JavaScript Strings ...
includes()Returns if a string contains a specified value indexOf()Returns the index (position) of the first occurrence of a value in a string lastIndexOf()Returns the index (position) of the last occurrence of a value in a string