C# StringBuilder文件维护格式

在c#中，如何将包含多行的stringbuilder导出到文件中，并对这些行进行绘制。这是我的密码：

StringBuilder builder = new StringBuilder();
using (SqlCommand command = new SqlCommand(consulta, SqlConn))
{
  using (SqlDataReader reader = command.ExecuteReader())
  {
    while (reader != null && reader.Read())
    {
      builder.AppendFormat("{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}", Convert.ToString(reader[0]), reader.GetDateTime(1).ToString("yyyy-MM-dd"), reader.GetDateTime(2).ToString("yyyy-MM-dd"), Convert.ToString(reader[3]), Convert.ToString(reader[4]), "06", Convert.ToString(reader[5]), Convert.ToString(reader[6]), Convert.ToString(reader[7]));
    }
  }
}

这里是我保存文件的地方，但它不尊重行

File.WriteAllText(saveFileDialog1.FileName, builder.ToString());

---

您需要使用

AppendLine

方法插入换行符：

builder.AppendFormat(...);
builder.AppendLine();
builder.AppendFormat(...);

---

需要换行符的地方。

需要使用

AppendLine

方法插入换行符：

builder.AppendFormat(...);
builder.AppendLine();
builder.AppendFormat(...);

---

需要换行的地方。

可以使用Environment.NewLine在生成器中的每行末尾添加新行

builder.AppendFormat("{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}{9}", Convert.ToString(reader[0]), reader.GetDateTime(1).ToString("yyyy-MM-dd"), reader.GetDateTime(2).ToString("yyyy-MM-dd"), Convert.ToString(reader[3]), Convert.ToString(reader[4]), "06", Convert.ToString(reader[5]), Convert.ToString(reader[6]), Convert.ToString(reader[7]), Environment.NewLine);

---

可以使用Environment.NewLine在生成器中向每一行的末尾添加新行

builder.AppendFormat("{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}{9}", Convert.ToString(reader[0]), reader.GetDateTime(1).ToString("yyyy-MM-dd"), reader.GetDateTime(2).ToString("yyyy-MM-dd"), Convert.ToString(reader[3]), Convert.ToString(reader[4]), "06", Convert.ToString(reader[5]), Convert.ToString(reader[6]), Convert.ToString(reader[7]), Environment.NewLine);

---

您在字符串生成器中看到的新行在哪里？试试这个：

while (reader != null && reader.Read())
{
     builder.AppendFormat("{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}{9}", Convert.ToString(reader[0]), reader.GetDateTime(1).ToString("yyyy-MM-dd"), reader.GetDateTime(2).ToString("yyyy-MM-dd"), Convert.ToString(reader[3]), Convert.ToString(reader[4]), "06", Convert.ToString(reader[5]), Convert.ToString(reader[6]), Convert.ToString(reader[7]), Environment.NewLine);
}

---

您在字符串生成器中看到的新行在哪里？试试这个：

while (reader != null && reader.Read())
{
     builder.AppendFormat("{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}{9}", Convert.ToString(reader[0]), reader.GetDateTime(1).ToString("yyyy-MM-dd"), reader.GetDateTime(2).ToString("yyyy-MM-dd"), Convert.ToString(reader[3]), Convert.ToString(reader[4]), "06", Convert.ToString(reader[5]), Convert.ToString(reader[6]), Convert.ToString(reader[7]), Environment.NewLine);
}

---

如果这样做效率更高、更简单，则不会避免不必要地使用

StringBuilder

以及为中间

String

分配内存的开销

我还添加了额外的

AppendLine

，用新行分隔行

using (var writer = new StreamWriter(saveFileDialog1.FileName))
{
    using (SqlCommand command = new SqlCommand(consulta, SqlConn))
    {
        using (SqlDataReader reader = command.ExecuteReader())
        {
            while (reader != null && reader.Read())
            {
                writer.AppendFormat(
"{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}", 
                    Convert.ToString(reader[0]),
                    reader.GetDateTime(1).ToString("yyyy-MM-dd"),
                    reader.GetDateTime(2).ToString("yyyy-MM-dd"),
                    Convert.ToString(reader[3]),
                    Convert.ToString(reader[4]), 
                    "06",
                    Convert.ToString(reader[5]),
                    Convert.ToString(reader[6]),
                    Convert.ToString(reader[7]));
                writer.AppendLine();
           }
       }
    }
}

我还建议您可以像这样提高代码的可读性，尽管这可能是主观的

using (var writer = new StreamWriter(saveFileDialog1.FileName))
{
    using (SqlCommand command = new SqlCommand(consulta, SqlConn))
    {
        using (SqlDataReader reader = command.ExecuteReader())
        {
            while (reader != null && reader.Read())
            {
                writer.AppendFormat("{0, -7}", reader[0]);
                writer.AppendFormat("{0:yyyy-MM-dd, -12}", reader.GetDateTime(1));
                writer.AppendFormat("{0:yyyy-MM-dd, -11}", reader.GetDateTime(2));
                writer.AppendFormat("{0, -19}", reader.[3]);
                writer.AppendFormat("{0, -12}06", reader.[4]);
                writer.AppendFormat("{0, -11}, reader.[5]);
                writer.AppendFormat("{0, -6}, reader.[6]);
                writer.AppendFormat("{0, -10}, reader.[7]);
                writer.AppendLine();
           }
       }
    }
}

---

如果这样做效率更高、更简单，则不会避免不必要地使用

StringBuilder

以及为中间

String

分配内存的开销

我还添加了额外的

AppendLine

，用新行分隔行

using (var writer = new StreamWriter(saveFileDialog1.FileName))
{
    using (SqlCommand command = new SqlCommand(consulta, SqlConn))
    {
        using (SqlDataReader reader = command.ExecuteReader())
        {
            while (reader != null && reader.Read())
            {
                writer.AppendFormat(
"{0,-5}  {1,-10}  {2,-10} {3,-18} {4,-10}  {5,-2}  {6,-10} {7,-5} {8,-10}", 
                    Convert.ToString(reader[0]),
                    reader.GetDateTime(1).ToString("yyyy-MM-dd"),
                    reader.GetDateTime(2).ToString("yyyy-MM-dd"),
                    Convert.ToString(reader[3]),
                    Convert.ToString(reader[4]), 
                    "06",
                    Convert.ToString(reader[5]),
                    Convert.ToString(reader[6]),
                    Convert.ToString(reader[7]));
                writer.AppendLine();
           }
       }
    }
}

我还建议您可以像这样提高代码的可读性，尽管这可能是主观的

using (var writer = new StreamWriter(saveFileDialog1.FileName))
{
    using (SqlCommand command = new SqlCommand(consulta, SqlConn))
    {
        using (SqlDataReader reader = command.ExecuteReader())
        {
            while (reader != null && reader.Read())
            {
                writer.AppendFormat("{0, -7}", reader[0]);
                writer.AppendFormat("{0:yyyy-MM-dd, -12}", reader.GetDateTime(1));
                writer.AppendFormat("{0:yyyy-MM-dd, -11}", reader.GetDateTime(2));
                writer.AppendFormat("{0, -19}", reader.[3]);
                writer.AppendFormat("{0, -12}06", reader.[4]);
                writer.AppendFormat("{0, -11}, reader.[5]);
                writer.AppendFormat("{0, -6}, reader.[6]);
                writer.AppendFormat("{0, -10}, reader.[7]);
                writer.AppendLine();
           }
       }
    }
}

---

builder.AppendFormat不中断行？调试时，请在

writealText

之前中断。文本视图显示什么？那可能是你的问题。如果有问题，您只需在字符串格式的末尾添加一个

\n

。@thantos同意。另一个选项-make

builder.AppendLine（）calli用AppendLine（string.Format（…）解析了它。我没有违反规定。对不起，为什么不直接写入
文件流
，中间
StringBuilder
有什么意义？它会无故导致内存分配成本。builder.AppendFormat不会中断行？调试时，请在
writealltext
之前中断。文本视图显示什么？那可能是你的问题。如果有问题，您只需在字符串格式的末尾添加一个
\n
。@thantos同意。另一个选项-make
builder.AppendLine（）calli用AppendLine（string.Format（…）解析了它。我没有违反规定。对不起，为什么不直接写入
文件流
，中间
StringBuilder
有什么意义？它会无缘无故地产生内存分配成本。