【Dart学习】--Dart之数字(num)相关方法总结

用法一（figureA）
```
int figureA = -93;
```
- 是否为负数
```
print(figureA.isNegative);
```
- figureA是否是有限的
```
print(figureA.isFinite);
```
- figureA是否正无穷大或负无穷大
```
 print(figureA.isInfinite);
```
用法二（figureB）
```
double figureB = 64.742;
```
- 返回figureB的符号，-1.0:值小于0、+1.0:值大于0、-0.0/0.0/NaN:值是其本身
```
print(figureB.sign);
```
- 返回figureB运行时的类型
```
print(figureB.runtimeType);
```
- 返回figureB的哈希码
```
print(figureB.hashCode);
```
用法三（figureC）
```
int figureC = 13;
```
- figureC是否为奇数
```
print(figureC.isOdd);
```
- figureC是否为偶数
```
print(figureC.isEven);
```
- 返回figureC所占存储位
```
print(figureC.bitLength);
```

用法一（figureA）
```
int figureA = -93;
```
- 返回figureA的绝对值
```
print(figureA.abs());
```
- 返回figureA的字符串
```
print(figureA.toString());
```

用法二（figureB）
```
double figureB = 64.742;
```
- 返回figureB的整数值
```
print(figureB.toInt());
```
- 返回figureB的双精度值
```
print(figureB.toDouble());
```
- 返回大于figureB的双精度值
```
print(figureB.ceilToDouble());
```
- 返回小于figureB的双精度值
```
print(figureB.floorToDouble());
```
- 返回figureB四舍五入的双精度值
```
print(figureB.roundToDouble());
```
- 返回figureB保留几位小数的字符串
```
print(figureB.toStringAsFixed(2));
```
- 返回figureB保留几位小数后精确结果的字符串
```
print(figureB.toStringAsPrecision(3));
```
用法三（figureC）
```
int figureC = 31;
```
- figureC对比其他整数，0:相同、1:大于、-1:小于
```
print(figureC.compareTo(20));
```
- 将figureC控制在指定区间的整数
```
print(figureC.clamp(20, 25));
```
- 返回figureC转换成指定基数(进制)的字符串
```
print(figureC.toRadixString(16));
```
用法四（figureD）
```
int figureD = 12;
```
- 返回figureD与其他整数的最大公约数
```
print(figureD.gcd(18));
```
- 返回figureDg与其他整数的截取余数
```
print(figureD.remainder(18));
```
- 返回figureD几次幂值的字符串
```
print(figureD.toStringAsExponential(2));
```