在我脑后的某个地方,一个小小的声音告诉我“下面的C#代码闻起来”.

private const string STR_ConnectionString = "ConnectionString";
private readonly string upperCaseConnectionString = STR_ConnectionString.toupperInvariant();
// a lot further on
string keyAttributeValue = keyAttribute.Value;
if (keyAttributeValue.toupperInvariant().StartsWith(upperCaseConnectionString)) 
{
    // some C# code handling a key that starts with "ConnectionString"
}

常量STR_ConnectionString也用于代码中的其他位置.

如何摆脱气味？

您可以使用 overloaded StartsWith method获取StringComparison枚举值：

keyAttributeValue.StartsWith(STR_ConnectionString,StringComparison.OrdinalIgnoreCase) // or use StringComparison.InvariantCultureIgnoreCase here

import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(system.in);
        BigDecimal a;
        while(in.hasNextBigDecimal()) {
            a=in.nextBigDecimal();
            int  b=in.nextInt();
            String s=a.pow(b).stripTrailingZeros().toPlainString();   //最后成了字符串。
            if(s.startsWith("0")) { s=s.substring(1); } //startsWith()是判断字符串是否以某个字符串开头，若是，返回true，String.substring(int start)参数：start：要截取位置的索引。返回：从start开始到结束的字符串。
            System.out.println(s);
        }
    }
}

我试图处理以下角色：⨝( http://www.fileformat.info/info/unicode/char/2a1d/index.htm)

如果你检查一个以这个字符开头的空字符串,它总是返回true,这没有任何意义！这是为什么？

// visual studio 2008 hides lines that have this char literally (bug in visual studio?!?) so i wrote it's unicode instead.
char specialChar = (char)10781;
string specialString = specialChar.ToString();

// prints 1
Console.WriteLine(specialString.Length);

// prints 10781
Console.WriteLine((int)specialChar);

// prints false
Console.WriteLine(string.Empty.StartsWith("A"));

// both prints true WTF?!?
Console.WriteLine(string.Empty.StartsWith(specialString));
Console.WriteLine(string.Empty.StartsWith(((char)10781).ToString()));

您可以使用 ordinal StringComparison修复此错误：

来自MSDN文档：

When you specify either
StringComparison.Ordinal or
StringComparison.OrdinalIgnoreCase,
the string comparison will be
non-linguistic. That is,the features
that are specific to the natural
language are ignored when making
comparison decisions. This means the
decisions are based on simple byte
comparisons and ignore casing or
equivalence tables that are
parameterized by culture. As a result,
by explicitly setting the parameter to
either the StringComparison.Ordinal or
StringComparison.OrdinalIgnoreCase,
your code often gains speed,increases
correctness,and becomes more
reliable.

char specialChar = (char)10781;


    string specialString = Convert.ToString(specialChar);

    // prints 1
    Console.WriteLine(specialString.Length);

    // prints 10781
    Console.WriteLine((int)specialChar);

    // prints false
    Console.WriteLine(string.Empty.StartsWith("A"));

    // prints false
    Console.WriteLine(string.Empty.StartsWith(specialString,StringComparison.Ordinal));