StringBuilder的常用方法
在程序開發過程中,我們常常碰到字符串連接的情況,方便和直接的方式是通過"+"符號來實現,但是這種方式達到目的的效率比較低,且每執行一次都會創建一個String對象,即耗時,又浪費空間。使用StringBuilder類就可以避免這種問題的發生,下面就Stringbuilder的使用做個簡要的總結:
StringBuilder strB = new StringBuilder();
System.out.println("StringBuilder:"+strB.append("ch").append("111").append('c'));
//return "StringBuilder:ch111c"
System.out.println("String:"+strB.toString());
//return "String:ch111c"
System.out.println("StringBuilder.appendCodePoint:"+strB.appendCodePoint(2));
//return "StringBuilder.appendCodePoint:ch111c"
strB.setCharAt(2, 'd');
System.out.println("StringBuilder.setCharAt:" + strB);
//return "StringBuilder.setCharAt:chd11c"
System.out.println("StringBuilder.insertString:"+ strB.insert(2, "LS"));
//return "StringBuilder.insertString:chLSd11c"
System.out.println("StringBuilder.insertChar:"+ strB.insert(2, 'L'));
//return "StringBuilder.insertChar:chLLSd11c"
6、delete(int startIndex,int endIndex):刪除起始位置(含)到結尾位置(不含)之間的字符串
System.out.println("StringBuilder.delete:"+ strB.delete(2, 4));
//return "StringBuilder.delete:chSd11c"