js控制文本框输入的内容为（数字、字母、汉字）（二、js在函数中实现）

文章转载自http://blog.csdn.net/ffwangxiuwei/article/details/6308753

原文博主：ffwangxiuwei

找了好多天的键值对照，今天终于找到了！衷心感谢原文博主！

技术要领：onkeydown事件先于onkeyup事件被触发；当onkeydown事件return false时onkeyup事件将不会被触发，并且输入框中也不会有用户刚按下的这个字符，从而实现了屏蔽某些字符的目的。了解了这一事件触发原理，思想上应当有所延伸(比如鼠标的几个事件也会是这样的机制).....

onkeypress是在用户按下并放开任何字母数字键时发生。系统按钮（例如，箭头键和功能键）无法得到识别。

onkeyup 是在用户放开任何先前按下的键盘键时发生。

onkeydown 是在用户按下任何键盘键（包括系统按钮，如箭头键和功能键）时发生。

currKey=e.keyCode||e.which||e.charCode;

currKey >=65 && currKey <=90 //非功能键的输入范围

//屏蔽非数字和非退格符
function GetInput(){
var k = event.keyCode;
//48-57是大键盘的数字键，96-105是小键盘的数字键，8是退格符←
if ((k <= 57 && k >= 48) || (k <= 105 && k >= 96) || (k == 8)){
return true;
}else {
return false;
}
}
function Set(obj){
//即时处理输入框的内容,比如进行某些运算
}
<input type="text" value="1">
//-----------------------------------控制只能输入数字，小数点----------------------------------------
function GetInput() {//屏蔽非数字和非退格符
var k = event.keyCode;   //48-57是大键盘的数字键，96-105是小键盘的数字键，8是退格符←
if ((k == 46) || (k == 8) || (k == 189) || (k == 109) || (k == 190) || (k == 110) || (k >= 48 && k <= 57) || (k >= 96 && k <= 105) || (k >= 37 && k <= 40)) {
return true;
} else {
return false;
}
}

键值对照（如下）

keycode 8 = BackSpace BackSpace

keycode 9 = Tab Tab

keycode 12 = Clear

keycode 13 = Enter

keycode 16 = Shift_L

keycode 17 = Control_L

keycode 18 = Alt_L

keycode 19 = Pause

keycode 20 = Caps_Lock

keycode 27 = Escape Escape

keycode 32 = space space

keycode 33 = Prior

keycode 34 = Next

keycode 35 = End

keycode 36 = Home

keycode 37 = Left

keycode 38 = Up

keycode 39 = Right

keycode 40 = Down

keycode 41 = Select

keycode 42 = Print

keycode 43 = Execute

keycode 45 = Insert

keycode 46 = Delete

keycode 47 = Help

keycode 48 = 0 equal braceright

keycode 49 = 1 exclam onesuperior

keycode 50 = 2 quotedbl twosuperior

keycode 51 = 3 section threesuperior

keycode 52 = 4 dollar

keycode 53 = 5 percent

keycode 54 = 6 ampersand

keycode 55 = 7 slash braceleft

keycode 56 = 8 parenleft bracketleft

keycode 57 = 9 parenright bracketright

keycode 65 = a A

keycode 66 = b B

keycode 67 = c C

keycode 68 = d D

keycode 69 = e E EuroSign

keycode 70 = f F

keycode 71 = g G

keycode 72 = h H

keycode 73 = i I

keycode 74 = j J

keycode 75 = k K

keycode 76 = l L

keycode 77 = m M mu

keycode 78 = n N

keycode 79 = o O

keycode 80 = p P

keycode 81 = q Q at

keycode 82 = r R

keycode 83 = s S

keycode 84 = t T

keycode 85 = u U

keycode 86 = v V

keycode 87 = w W

keycode 88 = x X

keycode 89 = y Y

keycode 90 = z Z

keycode 96 = KP_0 KP_0

keycode 97 = KP_1 KP_1

keycode 98 = KP_2 KP_2

keycode 99 = KP_3 KP_3

keycode 100 = KP_4 KP_4

keycode 101 = KP_5 KP_5

keycode 102 = KP_6 KP_6

keycode 103 = KP_7 KP_7

keycode 104 = KP_8 KP_8

keycode 105 = KP_9 KP_9

keycode 106 = KP_Multiply KP_Multiply

keycode 107 = KP_Add KP_Add

keycode 108 = KP_Separator KP_Separator

keycode 109 = KP_Subtract KP_Subtract

keycode 110 = KP_Decimal KP_Decimal

keycode 111 = KP_Divide KP_Divide

keycode 112 = F1

keycode 113 = F2

keycode 114 = F3

keycode 115 = F4

keycode 116 = F5

keycode 117 = F6

keycode 118 = F7

keycode 119 = F8

keycode 120 = F9

keycode 121 = F10

keycode 122 = F11

keycode 123 = F12

keycode 124 = F13

keycode 125 = F14

keycode 126 = F15

keycode 127 = F16

keycode 128 = F17

keycode 129 = F18

keycode 130 = F19

keycode 131 = F20

keycode 132 = F21

keycode 133 = F22

keycode 134 = F23

keycode 135 = F24

keycode 136 = Num_Lock

keycode 137 = Scroll_Lock

keycode 187 = acute grave

keycode 188 = comma semicolon

keycode 189 = minus underscore

keycode 190 = period colon

keycode 192 = numbersign apostrophe

keycode 210 = plusminus hyphen macron

keycode 211 =

keycode 212 = copyright registered

keycode 213 = guillemotleft guillemotright

keycode 214 = masculine ordfeminine

keycode 215 = ae AE

keycode 216 = cent yen

keycode 217 = questiondown exclamdown

keycode 218 = onequarter onehalf threequarters

keycode 220 = less greater bar

keycode 221 = plus asterisk asciitilde

keycode 227 = multiply division

keycode 228 = acircumflex Acircumflex

keycode 229 = ecircumflex Ecircumflex

keycode 230 = icircumflex Icircumflex

keycode 231 = ocircumflex Ocircumflex

keycode 232 = ucircumflex Ucircumflex

keycode 233 = ntilde Ntilde

keycode 234 = yacute Yacute

keycode 235 = oslash Ooblique

keycode 236 = aring Aring

keycode 237 = ccedilla Ccedilla

keycode 238 = thorn THORN

keycode 239 = eth ETH

keycode 240 = diaeresis cedilla currency

keycode 241 = agrave Agrave atilde Atilde

keycode 242 = egrave Egrave

keycode 243 = igrave Igrave

keycode 244 = ograve Ograve otilde Otilde

keycode 245 = ugrave Ugrave

keycode 246 = adiaeresis Adiaeresis

keycode 247 = ediaeresis Ediaeresis

keycode 248 = idiaeresis Idiaeresis

keycode 249 = odiaeresis Odiaeresis

keycode 250 = udiaeresis Udiaeresis

keycode 251 = ssharp question backslash

keycode 252 = asciicircum degree

keycode 253 = 3 sterling

keycode 254 = Mode_switch