Index: trunk/ab5.0/ablib/src/system/string.sbp
===================================================================
--- trunk/ab5.0/ablib/src/system/string.sbp	(revision 670)
+++ trunk/ab5.0/ablib/src/system/string.sbp	(revision 671)
@@ -2,4 +2,9 @@
 '文字列変数の操作用
 
+/*!
+@brief Stringが内部で保持しているポインタを返す。
+@param[in] s 文字列。
+@return sの内部バッファへのポインタ、ただしsがNothingならNULL。
+*/
 Function StrPtr(s As String) As *Char
 	If Not ActiveBasic.IsNothing(s) Then
@@ -7,10 +12,15 @@
 	End If
 End Function
-'StringBuilder版はClasses/System/Text/StringBuilder.abに定義されている
-
-Function ZeroString(length As Long) As System.Text.StringBuilder
-	ZeroString = New System.Text.StringBuilder
-	ZeroString.Length = length
-End Function
+'StringBuilder版はClasses/System/Text/StringBuilder.abに定義されている。
+
+/*!
+@brief 指定した長さの空文字(\0)を持つ文字列を作成する。
+@param[in] length 長さ
+@return Legnth = lengthとなっている文字列。
+*/
+Function ZeroString(length As Long) As String 
+	ZeroString = New String(0 As Char, length) 
+End Function 
+
 
 Function MakeStr(psz As PSTR) As String
@@ -40,5 +50,5 @@
 		Dim lenMBS = WideCharToMultiByte(CP_ACP, 0, wcsSrc, (len As DWord) As Long, 0, 0, 0, 0)
 		mbsDst = _System_AllocForConvertedString(SizeOf (CHAR) * lenMBS) As PSTR
-		GetMBStr = WideCharToMultiByte(CP_ACP, 0, wcsSrc, (wcsSrc As DWord) As Long, mbsDst, lenMBS, 0, 0) As SIZE_T
+		GetMBStr = WideCharToMultiByte(CP_ACP, 0, wcsSrc, (len As DWord) As Long, mbsDst, lenMBS, 0, 0) As SIZE_T
 	End Function