我正在嘗試使用 PInvoke 綁定此 C 函數。bool GuiTextBox(Rectangle bounds, char *text, int textSize, bool editMode);這是 PInvoke 簽名。[DllImport(nativeLibName,CallingConvention = CallingConvention.Cdecl)]public static extern bool GuiTextBox(Rectangle bounds,
string text,
int textSize,
bool freeEdit);當我嘗試使用它時，字符串不會被修改。我嘗試將它作為 ref 傳遞，但是當我嘗試使用它時它會因嘗試讀取或寫入受保護的內存而崩潰。
1 回答
臨摹微笑
TA貢獻1982條經驗 獲得超2個贊
我希望它應該是這樣的：
// private : do not expose inner details;
// we have to manipulate with StringBuilder
[DllImport(nativeLibName,
CallingConvention = CallingConvention.Cdecl,
EntryPoint = "GuiTextBox",
CharSet = CharSet.Unicode)] //TODO: Provide the right encoding here
private static extern bool CoreGuiTextBox(Rectangle bounds,
StringBuilder text, // We allow editing it
int textSize,
bool freeEdit);
// Here (in the public method) we hide some low level details
// memory allocation, string manipulations etc.
public static bool CoreGuiTextBox(Rectangle bounds,
ref string text,
int textSize,
bool freeEdit) {
if (null == text)
return false; // or throw exception; or assign "" to text
StringBuilder sb = new StringBuilder(text);
// If we allow editing we should allocate enough size (Length) within StringBuilder
if (textSize > sb.Length)
sb.Length = textSize;
bool result = CoreGuiTextBox(bounds, sb, sb.Length, freeEdit);
// Back to string (StringBuilder can have been edited)
// You may want to add some logic here; e.g. trim trailing '\0'
text = sb.ToString();
return result;
}
- 1 回答
- 0 關注
- 119 瀏覽
添加回答
舉報
0/150
提交
取消