input: Write a function to convert a given Python program to a C# program. The input is a Python function, and the output should be the equivalent C# function. If the input is empty, return an empty string.
  assert convert_to_csharp("def power(x, y):\n    if y == 0:\n        return 1\n    else:\n        return x * power(x, y - 1)")=="public int Power(int x, int y)\n{\n    if (y == 0)\n    {\n        return 1;\n    }\n    else\n    {\n        return x * Power(x, y - 1);\n    }\n}"
  assert convert_to_csharp("")==""
output: def convert_to_csharp(python_code):
      if not python_code:
          return ""
      lines = python_code.split("\n")
      csharp_code = []
      for line in lines:
          if line.startswith("def "):
              func_name, params = line[4:].split("(")
              params = params.rstrip("):")
              csharp_code.append(f"public int {func_name.capitalize()}({params})")
              csharp_code.append("{")
          elif line.startswith("    if "):
              csharp_code.append(f"    if ({line[6:].rstrip(':')})")
              csharp_code.append("    {")
          elif line.startswith("    else:"):
              csharp_code.append("    }")
              csharp_code.append("    else")
              csharp_code.append("    {")
          elif line.startswith("        return "):
              csharp_code.append(f"        return {line[14:]};")
          elif line.startswith("    return "):
              csharp_code.append(f"    return {line[10:]};")
      csharp_code.append("    }")
      csharp_code.append("}")
      return "\n".join(csharp_code)