double m = 78.5;

//將基本類型轉(zhuǎn)換為字符串

String str1 =String.valueOf(m);

System.out.println("m 轉(zhuǎn)換為String型后與整數(shù)20的求和結(jié)果為： "+(str1+20));

String str = "180.20";

Double a =Double.valueOf(str);

System.out.println("str 轉(zhuǎn)換為double型后與整數(shù)20的求和結(jié)果為： "+(a+20));

}

}