String are immutable in Java. You can't change them. You need to create a new string with the character replaced. String myName = "domanokz"; String newName= myName.substring(0,4)+'x'+myName.substring(5); or you can use a StringBuilder: StringBuilder myName =newStringBuilder("domanok...
The index of the first character is 0, while the index of the last character is length()-1. For example, the following code gets the character at index 9 in a string: String anotherPalindrome = "Niagara. O roar again!"; char aChar = anotherPalindrome.charAt(9); Indices begin at 0...
public String replace(char oldChar, char newChar); 1. Returns a string resulting from replacing all occurrences of {@code oldChar} in this string with {@code newChar}. If the character {@code oldChar} does not occur in the character sequence represented by this {@code String} object, t...
replace和replaceAll是编程中经常用到的替换函数,成功返回一个新的替换后的字符串,失败则返回原始字符串,它们都是替换字符串所有的符合规则的子串,但replaceAll接受正则表达式,所以对于普通的字符(不含正则)替换结果是一样的,但对于特殊的字符替换的经过则大相径庭。 1替换中特殊符号处理 开发中经常遇到语言中的特殊符号...
System.out.println(c_low);charc_up=Character.toUpperCase(c_low); str=str.replaceFirst(String.valueOf(c_low), String.valueOf(c_up)); System.out.println(str);//使用String的replace(oldChar,newChar)str1=str1.replace('b','a');
This class contains static methods for performing various operations on Strings. For example, this class has methods for counting the number of occurrences of a particular character in a String, and methods for splitting a String into elements that were separated by a specific character. ...
Stringstr="abc ABC 123 abc";StringstrNew=str.replace(" ",""); Copy Output abcABC123abc Remove a Substring from a String in Java You can remove only the first occurrence of a character or substring from a string in Java by using thereplaceFirst()method to replace the character or substri...
Return a new string where all "l" characters are replaced with "p" characters: String myStr = "Hello"; System.out.println(myStr.replace('l', 'p')); Try it Yourself » Definition and UsageThe replace() method searches a string for a specified character, and returns a new string whe...
replace各个方法的定义 一、replaceFirst方法 public String replaceFirst(String regex, String replacement) { return Pattern.compile(regex).matcher(this).replaceFirst(replacement); } 二、replace方法 public String replace(CharSequence target, CharSequence replacement) { ...
true如果字串是空的,或只Character#isWhitespace(int) white space包含程式代碼點,則傳回 ,否則false為。 IsEmpty true如果 為 ,則傳回 ,且只有在 為時 #length()0。 JniIdentityHashCode 類別String 代表字元字串。 (繼承來源 Object) JniPeerMembers 類別String 代表字元字串。 PeerReference 類別String ...