TextBox输入控制代码

C#控制TextBox输入的源代码:

       public static void KeyPressUFloat(object sender, KeyPressEventArgs e,int decCount)
        ...{
            TextBox txtBox = (TextBox)sender;
            int curPos = txtBox.SelectionStart; // 当前光标位置
            int pointPos = txtBox.Text.LastIndexOf(''.''); // 小数点位置
            // 输入位置在两位小数点后，不允许输入
            if ((pointPos > 0) && (curPos > (pointPos + decCount)))
            ...{
                if (e.KeyChar != '''')
                ...{
                    e.Handled = true;
                }

                return;
            }
            try
            ...{
                string strInt = txtBox.Text.Trim().Substring(0, curPos);
                string strDec = "";

                if (pointPos < 0)
                ...{
                    strDec = ".00";
                }
                else
                ...{
                    // 读取并规范化小数部分
                    strDec = txtBox.Text.Trim().Substring(pointPos);
                    if (strDec.Length > decCount + 1)
                    ...{
                        strDec = strDec.Substring(0, decCount + 1);
                    }
                    else
                    ...{
                        strDec = strDec.PadRight(decCount + 1, ''0'');
                    }
                }

                // 检测输入的字符
                if ((e.KeyChar < ''0'' || e.KeyChar > ''9'') &&
                    (e.KeyChar != ''.'') && (e.KeyChar != ''''))
                ...{
                    e.Handled = true;
                }
                else if (e.KeyChar == ''.'')
                ...{
                    // 输入了小数点
                    e.Handled = true;
                    if (strInt.Length == 0)
                    ...{
                        strInt = "0";
                    }

                    // 消除整数部分的小数点
                    if (strInt.IndexOf(".") != -1)
                    ...{
                        strInt = strInt.Remove(strInt.IndexOf(''.''));
                    }

                    txtBox.Text = strInt + strDec;
                    txtBox.SelectionStart = curPos;
                }
                else
                ...{
                    // 输入数字的操作
                    e.Handled = false;
                    if (curPos > pointPos)
                    ...{
                        // 小数点后，覆盖选择的后一个字符
                        txtBox.SelectionLength = 1;
                    }
                    else if (curPos == pointPos)
                    ...{
                        //txtBox.SelectionStart = curPos;
                        //SendKeys.Send(e.KeyChar.ToString());
                        // 输入位置在小数点之前的处理
                        if (txtBox.Text.Trim().Length == txtBox.MaxLength)
                        ...{
                            strDec = strDec.Remove(1, 1);
                            strDec = strDec.Insert(1, e.KeyChar.ToString());
                            txtBox.Text = strInt + strDec;
                            curPos += 2;
                            e.Handled = true;
                            txtBox.SelectionStart = curPos;
                        }
                        else
                        ...{
                            txtBox.SelectionStart = curPos;
                        }
                    }

                    if (pointPos < 0)
                    ...{
                        txtBox.Text = strInt + strDec;
                        pointPos = txtBox.Text.LastIndexOf(''.''); // 小数点位置
                    }

                    if ((curPos < pointPos) &&
                        (txtBox.Text.Trim().Length == txtBox.MaxLength))
                    ...{
                        txtBox.SelectionLength = 1;
                    }

                    txtBox.SelectionStart = curPos;
                }
            }
            catch (Exception)
            ...{
                throw new Exception("Internal error : UFloat");
            }

        }

 注: 本代码参照:              编程中国 http://www.bc-cn.net
                                          作者： C_B_Lu QQ：184118549
                                           时间： 2007-9-4 编程论坛首发