在 C# 中将字符串转换为 2 位小数的最有效方法
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Most efficient way to convert a string to 2 decimal places in C#
提问by Murtaza Mandvi
I have a stringwhich needs a decimal place inserted to give a precision of 2.
我有一个string需要插入小数位才能得到 2 的精度。
3000 => 30.00
300 => 3.00
30 => .30
采纳答案by Daniel Brückner
Given a string input, convert to integer, divide by 100.0 and use String.Format() to make it display two decimal places.
给定一个字符串输入，转换为整数，除以 100.0 并使用 String.Format() 使其显示两位小数。
String.Format("{0,0:N2}", Int32.Parse(input) / 100.0)
Smarter and without converting back and forth - pad the string with zeros to at least two characters and then insert a point two characters from the right.
更智能且无需来回转换 - 用零填充字符串至至少两个字符，然后从右侧插入一个点两个字符。
String paddedInput = input.PadLeft(2, '0')
padedInput.Insert(paddedInput.Length - 2, ".")
Pad to a length of three to get a leading zero. Pad to precision + 1 in the extension metheod to get a leading zero.
填充到长度为 3 以获得前导零。在扩展方法中填充到 precision + 1 以获得前导零。
And as an extension method, just for kicks.
作为一种扩展方法，只是为了踢。
public static class StringExtension
{
public static String InsertDecimal(this String @this, Int32 precision)
{
String padded = @this.PadLeft(precision, '0');
return padded.Insert(padded.Length - precision, ".");
}
}
// Usage
"3000".InsertDecimal(2);
Note: PadLeft() is correct.
注意：PadLeft() 是正确的。
PadLeft() '3' => '03' => '.03'
PadRight() '3' => '30' => '.30'
回答by Tarion
Use tryParse to avoid exceptions.
使用 tryParse 来避免异常。
int val;
if (int.Parse(input, out val)) {
String.Format("{0,0:N2}", val / 100.0);
}
回答by Tarion
here's very easy way and work well.. urValue.Tostring("F2")
这是非常简单的方法并且效果很好.. urValue.Tostring("F2")
let say.. int/double/decimal urValue = 100; urValue.Tostring("F2"); result will be "100.00"
比方说.. int/double/decimal urValue = 100; urValue.Tostring("F2"); 结果将是“100.00”
so F2 is how many decimal place u want if you want 4 place, then use F4
所以F2是你想要的小数位数，如果你想要4位，然后使用F4
