$num = 10.4567;
### 第一種：利用round()對浮點數進行四舍五入
```
echo round($num,2); //10.46
```
### 第二種：利用sprintf格式化字符串
```
$format_num = sprintf("%.2f",$num);
echo $format_num; //10.46
```
### 第三種：利用千位分組來格式化數字的函數number_format()
```
echo number_format($num, 2); //10.46
```
#### 或者如下
```
echo number_format($num, 2, '.', ''); //10/46
```
