c#中设置像数量，价格，金额等的textbox的限制条件，用户只能输入数字或小数

 1        #region 设置数量等textbox控件样式及限制条件（具体调用的方法就是重写或直接调用ShieldNumberTextBoxOtherKeys函数）

 2 

 3         /// <summary>

 4         /// 屏蔽数字textbox的其他字符串

 5         /// </summary>

 6         /// <param name="sender"></param>

 7         /// <param name="e"></param>

 8         public virtual void tBoxNumbers_KeyDown(object sender, KeyEventArgs e)

 9         {

10             e.SuppressKeyPress = true;

11 

12             switch (e.KeyCode)

13             {

14                 case Keys.D0:

15                 case Keys.D1:

16                 case Keys.D2:

17                 case Keys.D3:

18                 case Keys.D4:

19                 case Keys.D5:

20                 case Keys.D6:

21                 case Keys.D7:

22                 case Keys.D8:

23                 case Keys.D9:

24                 case Keys.NumPad0:

25                 case Keys.NumPad1:

26                 case Keys.NumPad2:

27                 case Keys.NumPad3:

28                 case Keys.NumPad4:

29                 case Keys.NumPad5:

30                 case Keys.NumPad6:

31                 case Keys.NumPad7:

32                 case Keys.NumPad8:

33                 case Keys.NumPad9:

34                 case Keys.Back:

35                 case Keys.OemPeriod:

36                 case Keys.Delete:

37                 case Keys.Decimal:

38                     e.SuppressKeyPress = false;

39                     break;

40                 default:

41                     break;

42             }

43         }

44 

45         public virtual void tBoxNumbers_KeyPress(object sender, KeyPressEventArgs e)

46         {

47             TextBox tBox = sender as TextBox;

48             char c = e.KeyChar;

49 

50             if (c.ToString().Equals("."))

51             {

52                 if (tBox.Text.Length <= 0)

53                     e.Handled = true;           //小数点不能在第一位     

54                 else

55                 {

56                     float f;

57                     float oldf;

58                     bool b1 = false, b2 = false;

59                     b1 = float.TryParse(tBox.Text, out oldf);

60                     b2 = float.TryParse(tBox.Text + e.KeyChar.ToString(), out f);

61                     if (b2 == false)

62                     {

63                         if (b1 == true)

64                             e.Handled = true;

65                         else

66                             e.Handled = false;

67                     }

68                 }

69             }

70         }

71 

72         /// <summary>

73         /// 屏蔽数字textbox的其他字符串

74         /// </summary>

75         /// <param name="tbox">要屏蔽的textbox</param>

76         public virtual void ShieldNumberTextBoxOtherKeys(TextBox tbox)

77         {

78             tbox.ImeMode = ImeMode.Disable;

79             tbox.KeyDown += tBoxNumbers_KeyDown;

80             tbox.KeyPress += tBoxNumbers_KeyPress;

81         }

82 

83         #endregion