如何检查字符串字符是否为空格？

Question

我刚开始用C#编程.我正在尝试构建一个简单的Vigenere文本加密工具作为个人项目.

我的问题应该很容易解决,但它真的强调我找出错误.在我的代码中,我试图做一个简单的检查,看看我的字符串中的字符是否是一个空格; 我已经正确设置了我的if语句但它正跳过第一个测试并转移到else,即使第一个测试是真的.我非常喜欢这方面的一些帮助.

我的问题区域在底部.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

public class fun2013
{
public static void Main()
{
    Console.WriteLine("fun 2013");
    string UserName;
    do
    {
        Console.Write("LOGIN//: ");
        UserName = Console.ReadLine();
    }
    while(UserName != "Max");
    Console.WriteLine(("Hello ") + (UserName) + (", enter your key below."));

                //USER ENTERS TEXT AT THIS POINT

    string loweredPass = Console.ReadLine().ToLower();
        Console.WriteLine("Changing CASE...");
        Console.WriteLine(loweredPass);
    string Strippedpass = loweredPass.Replace(" ","");
        Console.WriteLine("STRIPPING SPACES...");
        Console.WriteLine(Strippedpass);
    int passLength = Strippedpass.Length;
        Console.WriteLine("Enter your message below.");
    string userMessage = Console.ReadLine();
    int MessageLength = userMessage.Length;

                //BEGIN PROCESSING STRINGS INTO ARRAYS

    string temp = "";
    StringBuilder bcon = new StringBuilder();
    char [] passArray = Strippedpass.ToCharArray();
    char [] messArray = userMessage.ToCharArray();
    string letterf = "";

    for(int i=0, j=0; j < (MessageLength); i++, j++)    //i used for key array, j used for message length
        {
        >>> if (messArray[i].ToString() == " ")
            {
                letterf = " ";
            }
        else if (messArray[i].ToString() != " ")
            {
                letterf = passArray[i].ToString();
            }
            if (i >= (passLength-1))    //array starts at value 0, length check starts at 1. Subtract 1 to keep them equal
                {i = -1;}   //-1 is used so it will go back to value of 0 on next loop
        temp = letterf;
        bcon.Append(temp);
        }

    Console.WriteLine();
    Console.WriteLine(bcon);


    Console.WriteLine("Press ENTER to continue...");
        Console.ReadLine(); //KILL APPLICATION
}
}

感谢大家的帮助,但经过进一步检查后,我注意到我在for循环中出错了.我使用与键数组(int i)相同的间隔重置消息数组读取器.我改为使用正确的整数"j".我还将"temp"字符串更新程序和字符串构建器放入循环中的每个if语句中.它现在正常运行.

    for (int i=0, j=0; j < (MessageLength); i++, j++)    //i used for key array, j used for message length
    {

    if (messArray[j].ToString() != " ")
        {
            letterf = passArray[i].ToString();
            temp = letterf;
            bcon.Append(temp);
        }

    else if (messArray[j].ToString() == " ")
        {
            letterf = " ";
            temp = letterf;
            bcon.Append(temp);
        }

    if (i >= (passLength-1))    //array starts at value 0, length check starts at 1. Subtract 1 to keep them equal
        {i = -1;}   //-1 is used so it will go back to value of 0 on next loop
    }

Answer 1

Char.IsWhiteSpace(炭)

另见String.IsNullOrEmpty或String.IsNullOrWhiteSpace.