string 字符串 3 位小数
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String 3 decimal places
提问by Alex
Example 1
示例 1
Dim myStr As String = "38"
I want my result to be 38.000...
我希望我的结果是38.000...
Example 2
示例 2
myStr = "6.4"
I want my result to be 6.400
我希望我的结果是 6.400
What is the best method to achieve this? I want to format a stringvariable with atleast three decimalplaces.
实现这一目标的最佳方法是什么？我想用至少三位小数来格式化字符串变量。
回答by GJKH
Use FormatNumber:
使用FormatNumber：
Dim myStr As String = "38"
MsgBox(FormatNumber(CDbl(myStr), 3))
Dim myStr2 As String = "6.4"
MsgBox(FormatNumber(CDbl(myStr2), 3))
回答by Jodrell
So if you have
所以如果你有
Dim thirtyEight = "38"
Dim sixPointFour = "6.4"
Then, the best way to parse those to a numeric type is, Double.Parseor Int32.Parse, you should keep your data typed until you want to display it to the user.
然后，将它们解析为数字类型的最佳方法是，Double.Parse或者Int32.Parse，您应该保持数据的类型，直到您想将其显示给用户。
Then, if you want to format a string with 3 decimal places, do somthing like String.Format("{0:N3}", value).
然后，如果您想用 3 个小数位格式化字符串，请执行类似String.Format("{0:N3}", value).
So, if you want a quick hack for the problem,
所以，如果你想快速解决这个问题，
Dim yourString = String.Format("{0:N3}", Double.Parse("38"))
would do.
会做。
回答by giacomelli
Take a look on "Standard Numeric Format Strings"
float value = 6.4f;
Console.WriteLine(value.ToString("N3", CultureInfo.InvariantCulture));
// Displays 6.400
回答by Tony Hopkinson
In pseudo code
在伪代码中
decpoint = Value.IndexOf(".");
If decpoint < 0
return String.Concat(value,".000")
else
return value.PadRight(3 - (value.length - decpoint),"0")
If it's string keep it as a string. If it's a number pass it as one.
如果它是字符串，请将其保留为字符串。如果是数字，则将其作为一传递。
