C# 当我试图打开文件时，为什么文件中的空白区域丢失

我编写了一个小代码来打开文件。我的文件内容如下：每行长度为94个字符，行终止符为\r和\n

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

101111111111010190542A094101
900000000001000000000000000000000000000000000000000000000000000000000000

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

//这篇文章也是如此

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

101 111111111111010190608A094101
52001 1 CCD1 101019101019 111100002000001 6201110000251 00000000011 1 1 0111000020000001 820000000100111000020000000000000000000000011 111000020000001 90000001000000010011100020000000000001000000000000000000

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

---

但是我没有在这里遇到错误。谁能告诉我为什么我的第一次尝试是

File.ReadAllLines

，并担心以后的行长度

您没有收到错误，因为没有任何问题。但是，您需要处理

str.Length%94！=0

因为

ReadToEnd

将在字符串中包含换行符，这就是为什么

mod 94

不起作用的原因。另一种方法是读取每一行（使用

ReadLine

）并检查长度

ReadLine

会删除换行符。

这94个字符包括或不包括换行符吗？字符串

“a\r\nb”

的长度为四个字符，而不是两个。基于完整文件内容验证行长度似乎有点脆弱。例如，文件是否以

\r\n

对结尾。我更愿意单独阅读这些行，并验证每行的修剪长度

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

更新
您可以通过将内容与预期的行长度进行匹配来验证内容：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

public static bool StringIsValid(string input, int expectedLineLength)
{
    return input.Replace("\r\n", "").Length % expectedLineLength == 0;
}

// called like so:
if (StringIsValid(str, 94))
{
   // do something
}

但这并不十分准确。假设我们需要4个字符的字符串：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

string input = "abcd\r\nabcd\r\nabcd";
bool isValid = StringIsValid(input, 4); // returns true

看起来不错。但是，考虑一下：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

string input = "abcd\r\nabcd\r\nabcd";
bool isValid = StringIsValid(input, 6); // returns true

这也返回true，因为我们检查的唯一一件事是字符串的总长度（在删除换行符后）可以均匀地拆分为6个字符的行。可以使用12个字符的字符串，但这并不意味着它实际上由6个字符长的行组成。因此，更好的方法是检查线的长度。您可以一行一行地读取数据，验证数据并将其添加到输出中（如果正常）：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

private static bool LineHasCorrectLength(string line, int expectedLineLength)
{
    return line.Length == expectedLineLength;
}

// usage:
using (StreamReader reader = File.OpenText("thefile.txt"))
{
    while (!reader.EndOfStream)
    {
        string line = reader.ReadLine();
        if (LineHasCorrectLength(line, 94))
        {
            // add to output
        }
    }
}

…或者获取所有行，验证它们的长度，然后在它们验证正常时使用它们（在这种情况下，使用LINQ

all

extension方法）：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

更新2
根据您的评论，这应该适用于您的代码（使用上述示例代码中的

LinesHaveCorrectLength

方法，仅当所有行都具有预期长度时，该方法才会返回

true

）：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

更新3
非LINQ版本的

LinesHaveCorrectLength

：

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

private static bool LinesHaveCorrectLength(string[] lines, int expectedLineLength)
{
    foreach (string item in lines)
    {
        if (item.Length != expectedLineLength)
        {
            return false;
        }
    }
    return true;
}

这个适合我

     private void mnuOpen_Click(object sender, EventArgs e)
    {
        string strFilePath = string.Empty;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.FileName = string.Empty;
        openFileDialog1.RestoreDirectory = true;
        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            strFilePath = openFileDialog1.FileName;
            StreamReader sr = new StreamReader(strFilePath);
            string str = string.Empty;
            str = sr.ReadToEnd().Replace("\r", "").Replace("\n", "");
            sr.Close();
            if (str.Length % 94 == 0)
            {
                 //Do some thing
             }
           }

while (sr.Peek() >= 0)
{
  str = sr.ReadLine().Replace("\r", "").Replace("\n", "");
  length += str.Length;
}

---

您希望得到什么错误？顺便说一下，使用

File.ReadAllText

或

File.ReadAllLines

似乎是一个很好的例子。实际上，如果条件满足，我应该在网格中显示内容。这个条件对我的文件来说是真的，因为长度是188，但是当我调试1之后第一行的最后一个字符时，空白字符丢失了。如果我使用ReadLine，我只能读取一行，但是另一行呢，那么每行的长度将是96个字符，假设最后一行也以换行符结尾。@Dorababu:修改后，字符串将不再包含任何换行符，因此您需要借助字符串分析来填充网格。我仍然会选择逐行读取文件。但是如果我的文件中有两行以上的代码，那么它就可以工作。为什么会发生这种情况？如果代码不适用于我的所有情况，那么我可以更改它，但在少数情况下它可以工作，正如我所提到的，我是通过声明一个布尔变量得到它的