Javascript 如何仅限制特殊字符和(/、*、+;)
我们有一个文本字段。我们知道如何限制特殊字符。但我们只需要允许字母、数字和连字符(-),不需要特殊字符,除了(-)。给我任何想法 霉菌代码:Javascript 如何仅限制特殊字符和(/、*、+;),javascript,regex,html,validation,textbox,Javascript,Regex,Html,Validation,Textbox,我们有一个文本字段。我们知道如何限制特殊字符。但我们只需要允许字母、数字和连字符(-),不需要特殊字符,除了(-)。给我任何想法 霉菌代码: $('#pduration').keydown(function (e) { if (e.shiftKey || e.ctrlKey || e.altKey) { e.preventDefault(); } else { var key = e.ke
$('#pduration').keydown(function (e) {
if (e.shiftKey || e.ctrlKey || e.altKey) {
e.preventDefault();
} else {
var key = e.keyCode;
if (keyCodeEntered == 45) {
// Allow only 1 minus sign ('-')...
if ((elementRef.value) && (elementRef.value.indexOf('-') >= 0))
return false;
else
return true;
}
}
});
如果我们尝试此代码,它是限制光谱字符,但它允许-,/,+请指导我仅允许数字和字母以及仅允许连字符替换此部分:
if (keyCodeEntered == 45) {
// Allow only 1 minus sign ('-')...
if ((elementRef.value) && (elementRef.value.indexOf('-') >= 0))
return false;
{
else
return true;
}
为此:
// keys a-z,0-9 numpad keys 0-9 minus sign backspace
if ( ( key >= 48 && key <= 90 ) || ( key >= 96 && key <= 105 ) || key == 109 || key==8)
{
//return true;
}
else
{
//return false
}
})
//a-z键,0-9 numpad键0-9减号退格
如果((key>=48&&key=96&&key使用正则表达式模式匹配非常容易
对于JavaScript,我推荐,对于正则表达式,我推荐Rubular用于测试和学习
正则表达式模式如下所示:
/pattern/flags
**首先,声明一个正则表达式模式*
/<regex here>/
这将只捕获第一个字符
因为我们需要所有匹配的字符,所以我们为全局添加了标志g
,
它将返回匹配的字符。获取所有合法标志的最终模式如下:
/[a-zA-Z0-9-]/g
图案就是这样
为了检查某些内容是否包含非法字符,如您所问,您可以执行以下操作(两个示例都有效):
我已经使用了这个代码,它100%工作
<script type="text/javascript">
/* 48-57 - (0-9) NUMBERS
65-90 - (A-Z)
97-122 - (a-z)
8 - (BACKSPACE)
32 - (SPACE)
45 - '-' (MINUS, HYPHEN, DASH)
*/ // NOT ALLOW SPECIAL
function blockSpecialKeys(e) {
var Keys = e.keyCode;
return (
( Keys >= 65 && k <= 90 ) || // (A-Z)
( Keys >= 97 && k <= 122 ) || // (a-z)
( Keys == 8 ) || // (BACKSPACE)
( Keys == 32 ) || // (SPACE)
( Keys == 45 ) // '-' (MINUS, HYPHEN, DASH)
);
} // END OF blockSpecialKeys FUNCTION
</script>
<input type="text" ... remaining coding ... onKeyPress="return blockSpecialKeys(event);">
/*48-57-(0-9)个数字
65-90-(A-Z)
97-122-(a-z)
8-(退格)
32-(空间)
45-“-”(减号、连字符、破折号)
*///不允许特殊
功能块专用键(e){
var-Keys=e.keyCode;
报税表(
(键>=65&&k=97&&k给我一些想法?你试过解决这个问题吗。@unikorn谢谢回复,我们只知道我们需要的限制特殊字符,连字符除外。请将代码作为well@unikorn请指导我如何添加代码我们尝试过这样的$(函数(){$('#pno').keydown(函数(e){alert(“first”);var key=e.keyCode;如果((key>=48&&key=96&&key)您的代码工作正常,但退格功能对我不起作用。请指导我编辑代码以允许退格(keyCode 8)
/[a-zA-Z0-9-]/g
function verifyIllegalCharacters (inputString)
{
// Copy the results from replace to new string
// It now holds the original string, minus all legal characters.
// Since they were overwritten by "".
var newStr = inputString.replace(/[a-zA-Z0-9-]/g, "");
// If length is 0, all legal characters were removed,
// and no illegal characters remain.
return (newStr.length == 0);
}
function verifyIllegalCharacters (inputString)
{
// Same, but here we instead check for characters
// NOT matching the pattern. Above we capture all legal chars,
// here we capture all illegal chars by adding a ^ inside the class,
// And overwrite them with "".
var newStr = inputString.replace(/[^a-zA-Z0-9-]/g, "");
// If the lengths aren't equal, something was removed
// If something was removed, the string contained illegal chars.
// Returns true if no illegal chars, else false.
return (newStr.length == inputString.length);
}
<script type="text/javascript">
/* 48-57 - (0-9) NUMBERS
65-90 - (A-Z)
97-122 - (a-z)
8 - (BACKSPACE)
32 - (SPACE)
45 - '-' (MINUS, HYPHEN, DASH)
*/ // NOT ALLOW SPECIAL
function blockSpecialKeys(e) {
var Keys = e.keyCode;
return (
( Keys >= 65 && k <= 90 ) || // (A-Z)
( Keys >= 97 && k <= 122 ) || // (a-z)
( Keys == 8 ) || // (BACKSPACE)
( Keys == 32 ) || // (SPACE)
( Keys == 45 ) // '-' (MINUS, HYPHEN, DASH)
);
} // END OF blockSpecialKeys FUNCTION
</script>
<input type="text" ... remaining coding ... onKeyPress="return blockSpecialKeys(event);">