String str="123";

2个回答

public class Test{
public static void main(String[] arg) {
String str1="2.30";
BigDecimal bd=new BigDecimal(str1);
System.out.println(bd);
}
}

String str = "777.77";

BigDecimal big = new BigDecimal(str);

System.out.println("After Cast：" + big);

String string = "123";
Double double1 = Double.valueOf(string);
System.out.println(double1);

NumberFormat format = NumberFormat.getInstance();
Number number = format.parse("1,234");
double d = number.doubleValue();

sql数据类型decimal(18, 2) 转换decimal(18, 3)

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decimal system
Problem Description As we know , we always use the decimal system in our common life, even using the computer. If we want to calculate the value that 3 plus 9, we just import 3 and 9.after calculation of computer, we will get the result of 12. But after learning <<The Principle Of Computer>>,we know that the computer will do the calculation as the following steps: 1 computer change the 3 into binary formality like 11; 2 computer change the 9 into binary formality like 1001; 3 computer plus the two number and get the result 1100; 4 computer change the result into decimal formality like 12; 5 computer export the result; In the computer system there are other formalities to deal with the number such as hexadecimal. Now I will give several number with a kind of change method, for example, if I give you 1011(2), it means 1011 is a number in the binary system, and 123(10) means 123 if a number in the decimal system. Now I will give you some numbers with any kind of system, you guys should tell me the sum of the number in the decimal system. Input There will be several cases. The first line of each case contains one integers N, and N means there will be N numbers to import, then there will be N numbers at the next N lines, each line contains a number with such form : X1….Xn.(Y), and 0<=Xi<Y, 1<Y<=10. I promise you that the sum will not exceed the 100000000, and there will be at most 100 cases and the 0<N<=1000. Output There is only one line output case for each input case, which is the sum of all the number. The sum must be expressed using the decimal system. Sample Input 3 1(2) 2(3) 3(4) 4 11(10) 11(2) 11(3) 11(4) Sample Output 6 23

[问题地址](https://link.zhihu.com/?target=https%3A//www.w3cschool.cn/csharp/csharp-data-types.html%23 "") ![图片说明](https://pic3.zhimg.com/v2-810b6dfa80d9f1ca48352ee605e0681e_b.png) 我在Visual Studio上输出decimal和double的最大值、最小值只有一个确定值。 ![图片说明](https://pic3.zhimg.com/v2-55f11e5e1d6e7f3b361ef6ec571850ca_b.png)
mysql数据库decimal(5,2)的sql语句更新问题
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c#将一个对象转换成json
c#将一个对象转换成json class AllyRequestIO { /*//请求随机数 private String random { get; set; } //请求参数 private String iparams { get; set; }*/ public String token { get; set; } public int payType { get; set; } public Decimal amount { get; set; } public String use { get; set; } public String remark { get; set; } public String orgId { get; set; } public long merchantId { get; set; } public String pbucode { get; set; } public String accno { get; set; } public String accname { get; set; } public String bankcode { get; set; } public String ubankno { get; set; } public String cusno { get; set; } public int acctype { get; set; } } AllyRequestIO aio = new AllyRequestIO(); aio.token = "e993ffb0-54a7-4446-8b17-937f1454d214"; aio.payType = 1; aio.amount = (Decimal)111.00; aio.use = "余额充值"; aio.remark = "用户：超级管理员充值余额"; aio.orgId="DDA607C7-C875-4B3A-AA29-4D435F2A4295"; aio.merchantId = 1; aio.pbucode = "TEST"; aio.accno = "6225842255849524451"; aio.accname = "李四"; aio.bankcode = "CCB"; aio.ubankno = "衣冠庙支行"; aio.cusno = "3625"; aio.acctype = 2; 我要将aio转换成json，怎么做？

```import decimal print(decimal.Decimal(9.995)) ``` 请问这里的‘decimal’ 和‘Decimal’各代表的是什么？

System.out.println(list.get(0).get("sum(c.couponfee/100)")); BigDecimal sum = new BigDecimal((Double)(list.get(0).get("sum(c.couponfee/100)"))); BigDecimal max = new bigd /* for(int i=0;i<l.size();i++){ BigDecimal sum= new BigDecimal((Double)list.get(i).get("sum(c.couponfee/100)")); BigDecimal max = new BigDecima; BigDecimal min = new BigDecimal(l.get(i).get("min")) ; if(sum.compareTo(min)>0&&sum.compareTo(max)<0){ e.put("content","11"); } }*/ System.out.println(l); System.out.println(sum); max和min数据库存的decima类型，怎么转换和sum比大小啊？？ 更多 0
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Problem Description As we know , we always use the decimal system in our common life, even using the computer. If we want to calculate the value that 3 plus 9, we just import 3 and 9.after calculation of computer, we will get the result of 12. But after learning <<The Principle Of Computer>>,we know that the computer will do the calculation as the following steps: 1 computer change the 3 into binary formality like 11; 2 computer change the 9 into binary formality like 1001; 3 computer plus the two number and get the result 1100; 4 computer change the result into decimal formality like 12; 5 computer export the result; In the computer system there are other formalities to deal with the number such as hexadecimal. Now I will give several number with a kind of change method, for example, if I give you 1011(2), it means 1011 is a number in the binary system, and 123(10) means 123 if a number in the decimal system. Now I will give you some numbers with any kind of system, you guys should tell me the sum of the number in the decimal system. Input There will be several cases. The first line of each case contains one integers N, and N means there will be N numbers to import, then there will be N numbers at the next N lines, each line contains a number with such form : X1….Xn.(Y), and 0<=Xi<Y, 1<Y<=10. I promise you that the sum will not exceed the 100000000, and there will be at most 100 cases and the 0<N<=1000. Output There is only one line output case for each input case, which is the sum of all the number. The sum must be expressed using the decimal system. Sample Input 3 1(2) 2(3) 3(4) 4 11(10) 11(2) 11(3) 11(4) Sample Output 6 23
Incorrect decimal value

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SQL问题：select * from 出来的decimal数据类型的数据精度丢失

decimal system 的编写的方式
Problem Description As we know , we always use the decimal system in our common life, even using the computer. If we want to calculate the value that 3 plus 9, we just import 3 and 9.after calculation of computer, we will get the result of 12. But after learning <<The Principle Of Computer>>,we know that the computer will do the calculation as the following steps: 1 computer change the 3 into binary formality like 11; 2 computer change the 9 into binary formality like 1001; 3 computer plus the two number and get the result 1100; 4 computer change the result into decimal formality like 12; 5 computer export the result; In the computer system there are other formalities to deal with the number such as hexadecimal. Now I will give several number with a kind of change method, for example, if I give you 1011(2), it means 1011 is a number in the binary system, and 123(10) means 123 if a number in the decimal system. Now I will give you some numbers with any kind of system, you guys should tell me the sum of the number in the decimal system. Input There will be several cases. The first line of each case contains one integers N, and N means there will be N numbers to import, then there will be N numbers at the next N lines, each line contains a number with such form : X1….Xn.(Y), and 0<=Xi<Y, 1<Y<=10. I promise you that the sum will not exceed the 100000000, and there will be at most 100 cases and the 0<N<=1000. Output There is only one line output case for each input case, which is the sum of all the number. The sum must be expressed using the decimal system. Sample Input 3 1(2) 2(3) 3(4) 4 11(10) 11(2) 11(3) 11(4) Sample Output 6 23

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