FileStream: 文件“XXX”正由另一进程使用，因此该进程无法访问此文件

时间：2020-04-29 18:02:27 阅读：95 评论：0 收藏：0 [点我收藏+]

标签：readwrite users 打开 mamicode ons access mes 共享 code

1.现象说明（仅测试FileShare=ReadWrite时候的影响，FileAccess保持一致，如果FileAccess不一致的情况，另论，此处不讨论）：

a. FileAccess=Read, FileShare=ReadWrite未释放之后再打开文件：

FileStream file;
file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Read, FileShare.None);
}
catch (Exception ex)
{
    Console.WriteLine($"None:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Read, FileShare.Read);
}
catch (Exception ex)
{
    Console.WriteLine($"Read:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Read, FileShare.Write);
}
catch (Exception ex)
{
    Console.WriteLine($"Write:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
}
catch (Exception ex)
{
    Console.WriteLine($"ReadWrite:   {ex.Message}");
}

异常信息如下：

技术图片

b. 调整 FileAccess=Write, FileShare=ReadWrite未释放之后再打开文件：

FileStream file;
file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Write, FileShare.ReadWrite);
try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Write, FileShare.None);
}
catch (Exception ex)
{
    Console.WriteLine($"None:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Write, FileShare.Read);
}
catch (Exception ex)
{
    Console.WriteLine($"Read:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Write, FileShare.Write);
}
catch (Exception ex)
{
    Console.WriteLine($"Write:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.Write, FileShare.ReadWrite);
}
catch (Exception ex)
{
    Console.WriteLine($"ReadWrite:   {ex.Message}");
}

异常信息如下：

技术图片

c. 调整为FileAccess=ReadWrite, FileShare=ReadWrite未释放之后再打开文件：

FileStream file;
file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.None);
}
catch (Exception ex)
{
    Console.WriteLine($"None:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.Read);
}
catch (Exception ex)
{
    Console.WriteLine($"Read:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.Write);
}
catch (Exception ex)
{
    Console.WriteLine($"Write:   {ex.Message}");
}

try
{
    file = new FileStream(@"C:\Users\croot\Desktop\1.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
}
catch (Exception ex)
{
    Console.WriteLine($"ReadWrite:   {ex.Message}");
}