如何将 VB.NET 中的扩展移植到 C#？

Question

我在 VB.NET 中为 StringBuilder 编写了一个扩展，以添加一个 AppendFormattedLine 方法（因此我不必为换行符使用其中一个参数）：

Imports System.Runtime.CompilerServices
Public Module sbExtension
    <Extension()> _
    Public Sub AppendFormattedLine(ByVal oStr As System.Text.StringBuilder, _
                                   ByVal format As String, _
                                   ByVal arg0 As Object)
        oStr.AppendFormat(format, arg0).Append(ControlChars.NewLine)
    End Sub
    <Extension()> _
    Public Sub AppendFormattedLine(ByVal oStr As System.Text.StringBuilder, _
                                   ByVal format As String, ByVal arg0 As Object, _
                                   ByVal arg1 As Object)
        oStr.AppendFormat(format, arg0, arg1).Append(ControlChars.NewLine)
    End Sub
    <Extension()> _
    Public Sub AppendFormattedLine(ByVal oStr As System.Text.StringBuilder, _
                                   ByVal format As String, _
                                   ByVal arg0 As Object, _
                                   ByVal arg1 As Object, _
                                   ByVal arg2 As Object)
        oStr.AppendFormat(format, arg0, arg1, arg2).Append(ControlChars.NewLine)
    End Sub
    <Extension()> _
   Public Sub AppendFormattedLine(ByVal oStr As System.Text.StringBuilder, _
                                  ByVal format As String, _
                                  ByVal ParamArray args() As Object)
        oStr.AppendFormat(format, args).Append(ControlChars.NewLine)
    End Sub
End Module

Answer 1

我不会像这样嵌套string.Format() 调用。

您知道string.Format() 在幕后创建了一个新的StringBuilder 并调用它的AppendFormat() 方法吗？以上面的第一种方法为例，这应该会更有效：

sb.AppendFormat(format, arg0).Append(Environment.NewLine);

您也应该对 VB 代码进行相同的更改。

Answer 2

这是我想出的移植代码：

using System;
using System.Text;

public static class ExtensionLibrary
{
    public static void AppendFormattedLine(this StringBuilder sb, string format, object arg0)
    {
        sb.AppendFormat(format, arg0).Append(Environment.NewLine);
    }
    public static void AppendFormattedLine(this StringBuilder sb, string format, object arg0, object arg1)
    {
        sb.AppendFormat(format, arg0, arg1).Append(Environment.NewLine);
    }
    public static void AppendFormattedLine(this StringBuilder sb, string format, object arg0, object arg1, object arg2)
    {
        sb.AppendFormat(format, arg0, arg1, arg2).Append(Environment.NewLine);
    }
    public static void AppendFormattedLine(this StringBuilder sb, string format, params object[] args)
    {
        sb.AppendFormat(format, args).Append(Environment.NewLine);
    }
}

希望这对某人有用！

改进的代码，感谢 joel、luke 和 jason。

Answer 3

我以前从未使用过 Telerik 的代码转换器，但它的想法是这样的：

public class sbExtension
{
    [Extension()]
    public void AppendFormattedLine(System.Text.StringBuilder oStr, string format, object arg0)
    {
        oStr.AppendFormat(format, arg0).Append(ControlChars.NewLine);
    }
    [Extension()]
    public void AppendFormattedLine(System.Text.StringBuilder oStr, string format, object arg0, object arg1)
    {
        oStr.AppendFormat(format, arg0, arg1).Append(ControlChars.NewLine);
    }
    [Extension()]
    public void AppendFormattedLine(System.Text.StringBuilder oStr, string format, object arg0, object arg1, object arg2)
    {
        oStr.AppendFormat(format, arg0, arg1, arg2).Append(ControlChars.NewLine);
    }
    [Extension()]
    public void AppendFormattedLine(System.Text.StringBuilder oStr, string format, params object[] args)
    {
        oStr.AppendFormat(format, args).Append(ControlChars.NewLine);
    }
}


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