Example 2: Replacing a substring within a string // Replaces old characters with new characters in a stringfunctionreplaceString(oldChars, newChars, string){for(leti =0; i < string.length; ++i) { if(string.subs
substring 提取从 indexA 到 indexB(不包括)之间的字符。特别地: 如果indexA 等于 indexB,substring 返回一个空字符串。 如果省略 indexB,substring 提取字符一直到字符串末尾。 如果任一参数小于 0 或为 NaN,则被当作 0。 如果任一参数大于 stringName.length,则被当作 stringName.length。 如果indexA 大于 i...
JavaScript console.log() Javascript String substring() JavaScript String codePointAt() JavaScript String charAt() Javascript String toUpperCase() JavaScript StringThe JavaScript string is a primitive data type that represents textual data. For example, let name = "John"; Create JavaScript Strings...
string.substring(0); console.log(substring); //substring method example //StartIndex and EndIndex are equal var substring = string.substring(0,0); //"" //StartIndex is greater than endIndex var substring = string.substring(9,0); //Nothing but string.substring(0,9); //substrin...
Thesubstring()method does not change the original string. If start is greater than end, arguments are swapped: (4, 1) = (1, 4). Start or end values less than 0, are treated as 0. See Also: The split() Method The slice() Method ...
package com.example;public class MyClass {public static void main(String[] args){String test = "Hello World !";String subTest1 = test.substring(0,3);System.out.println("subTest:" + subTest1);String subTest2 = test.substring(0,test.length());System.out.println("subTest:" + subTest...
Example 实例 In this example we will use substring() to extract some characters from a string: 在本例中,我们将演示substring()从字符串中选取一些字符: var str="Hello world!" document.write(str.substring(3)) The output of the code above ...
string. Thissubstringfunction can accept two numbers, thestartand theend(exclusive) character position, respectively. In case the end value is smaller than the start, substring is smart enough toswapthe values before doing the string extraction. An example of substring is illustrated in this code ...
1:String.charAt(index)Tip：返回字符串指定位置的字符，index 为必须参数，类型为number（0到str.length-1之间，否则该⽅法返回空串）另外：str.charAt()即不带参数和str.charAt(NaN)均返回字符串的第⼀个字符";forexample：testString(){ let str = "z0a1b2c3d4e5f6h7g8k9X7Y8J";// index 1 consol...
JavaScript String slice() 方法示例 让我们举一个使用 slice() 方法的例子。 以下示例使用 slice() 方法获取电子邮件地址的本地部分: letemail ='john@example.com'letlocalPart = email.slice(0,email.indexOf('@')); console...