Javascript 在 React Native 中使用小数
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Using Decimals in React Native
提问by Nimila Hiranya
I have a state as value: 10.00and once I update it with some operation and add it to a <Text>the ".00" part gets trimmed off. If it was a value like 10.50, it'll be displayed as 10.5
我有一个状态value: 10.00，一旦我用一些操作更新它并将它添加到<Text>“.00”部分就会被修剪掉。如果它是一个像 10.50 这样的值，它将显示为 10.5
This is a issue as I want to display currency values. How to handle this?
这是一个问题，因为我想显示货币价值。如何处理？
回答by Nimila Hiranya
Found the answer. To have the value with decimal values, use toFixed()method.
找到了答案。要具有十进制值的值，请使用toFixed()方法。
Example:
例子：
var value = 10;
value = value.toFixed(2);
this.setState({subTotal: value});
The output would be: 10.00
输出将是：10.00
回答by Gaurav Vanani
here is another solution you can also try, what i need is don't allow to enter more than 2 decimal digits (after decimal point) and also shouldn't allow more than two decimal points or any other character.
这是您也可以尝试的另一种解决方案，我需要的是不允许输入超过 2 个十进制数字（小数点后），也不应允许超过两个小数点或任何其他字符。
ConTwoDecDigit=(digit)=>{
return digit.indexOf(".")>0?
digit.split(".").length>=2?
digit.split(".")[0]+"."+digit.split(".")[1].substring(-1,2)
: digit
: digit
}
<TextInput
value={this.state.salary}
onChangeText={value => this.setState({ salary: this.ConTwoDecDigit(value) })}
keyboardType={'decimal-pad'}
/>
回答by Pravin S.
If you don't want to show unnecessary zero after decimal points.
如果您不想在小数点后显示不必要的零。
_CalculateValue(value) {
if((value * 100.0).toFixed(3)<value * 100.0)
{
return (value * 100.0).toFixed(3)
}
return value * 100.0
}
Output:
输出：
10
17.890
12
783.120
56.009
