貞愛講

語言：C#
功能：string.Substring(startIndex, length)改良
原因：當StartIndex + length > string.Length時會發生錯誤，但程式執行時有時不知道字長度，造成錯誤，很麻煩，只好自己改良了
語法：
 public static string SubString(string strData, int startIndex, int length) 
        {
            int intLen = strData.Length;
            int intSubLen = intLen - startIndex;
            string strReturn; 

            if (length == 0)
                strReturn = "";
            else
            {
                if (intLen <= startIndex)
                    strReturn = "";
                else
                {
                    if (length > intSubLen)
                        length = intSubLen;

                    strReturn = strData.Substring(startIndex, length);
                }
            }
            return strReturn;
        }

語言：C#
功能：無條件捨去
語法：

public static double NoRound(double num, int post)
  {
         double nReturn;
         double nPow;
          if (post <= 0 )
          {
              nReturn = Math.Floor(num);
          }
          else
          {
              nPow = Math.Pow(10, post);
              nReturn = Math.Floor(num * nPow)/nPow;
          }
          return nReturn;
}

語言：C#

public static string ConvertDateToString(string strDate)    {         return DateTime.ParseExact(strDate, "yyyy/MM/dd", CultureInfo.CurrentCulture).ToString("yyyyMMdd");    }

public static string ConvertStringToDate(string strDate)     {         return DateTime.ParseExact(strDate, "yyyyMMdd", CultureInfo.CurrentCulture).ToString("yyyy/MM/dd");     }

 VB.ET及C# 程式碼轉換
推薦此網站：
http://labs.developerfusion.co.uk/

語言: C#
功能: FTP下載檔案
語法:

        public static StreamReader FtpDownLoad(Uri UriFpt, string strUserName, string strPassword)
        {
            FtpWebRequest request = (FtpWebRequest)WebRequest.Create(UriFpt);
            request.Method = WebRequestMethods.Ftp.DownloadFile;

            request.Credentials = new NetworkCredential(strUserName, strPassword);
            FtpWebResponse response = (FtpWebResponse)request.GetResponse();
            Stream responseStream = response.GetResponseStream();
            StreamReader reader = new StreamReader(responseStream, Encoding.Default);
            return reader;
        }

呼叫時

Form1:
BackgroundImage：挑一個不規則型狀的圖片
BackgroundImageLayout：Stretch
FormBorderStyle

語言：C#  
功能：將畫面所有TextBox都清為空白
輸入畫面如上，使用者將剛才輸入項全部清空

        private void button1_Click(object sender, EventArgs e)
        {
            foreach (Control c in Controls)
            {
                if (c is TextBox)
                    c.Text = "";
            }

C# TextBox電子郵件驗證

private void TextBox1_Validating(object sender, System.ComponentModel.CancelEventArgs e)
        {
            if (TextBox1.Text==string.Empty)
                errorProvider1.SetError(TextBox1, "");
            else
                if (!(Regex.IsMatch(TextBox1.Text,
                              @"^([a-zA-Z0-9_\-])([a-zA-Z0-9_\-\.]*)@(\[((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\.){3}|((([a-zA-Z0-9\-]+)\.)+))([a-zA-Z]{2,}|(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\])$")))
                {
                    errorProvider1.SetError(TextBox1, "電子郵件地址務必採用 abc@cccc.ccc.cc 的格式。");
                    e.Cancel = true;
                }
                else
                {
                    errorProvider1.SetError(TextBox1, "");
                    e.Cancel = false;
                }
        }

C#  TextBox只能夠輸入數字及小數點
private void InitializeComponent()

 this.TextBox1.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.TextBoxF_32B_2_KeyPress);

 private void TextBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            if (e.KeyChar.CompareTo('\b') == 0)
                e.Handled = false;
            else if ((e.KeyChar.CompareTo('0') < 0 || e.KeyChar.CompareTo('9') > 0) && !(e.KeyChar.CompareTo('.') == 0)) //比較輸入值的範圍是否超出數字
                e.Handled = true;// Handled 為是否鎖住輸入
        }

C# 使用ClickOnce 部署
無法指定安裝路徑，安裝後Access資料庫存放於何處
儲存在使用者 [Documents and Settings] 資料夾中的資料目錄
若想要知道正確路徑，程式碼：
if (ApplicationDeployment.IsNetworkDeployed)
 {
    ApplicationDeployment ad = ApplicationDeployment.CurrentDeployment;
    textBox1.Text = ad.DataDirectory.ToString();
 }

---

[Documents and Settings] \UserName\Local Settings\Apps\2.0\Data\.................目錄下