一、用
JS把全角转换成半角(不能转换标点符号)
<input type="text" size="10" maxlength="10"
onkeyup="
javascript:var t = ''; with(this.value) { for (var i = 0; i < length; i++) t += (65296 <= charCodeAt(i) && charCodeAt(i) <= 65305) ? String.fromCharCode(charCodeAt(i) - 65248) : charAt(i); } this.value = t;"
/>
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二、用JS把全角转换成半角的函数
<input name="n" type="text" id="n" onkeyup="CtoH(this);" />
<script>
function CtoH(obj)
{
var str=obj.value;
var result="";
for (var i = 0; i < str.length; i++)
{
if (str.charCodeAt(i)==12288)
{
result+= String.fromCharCode(str.charCodeAt(i)-12256);
continue;
}
if (str.charCodeAt(i)>65280 && str.charCodeAt(i)<65375)
result+= String.fromCharCode(str.charCodeAt(i)-65248);
else result+= String.fromCharCode(str.charCodeAt(i));
}
obj.value=result;
}
</script>
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三、用JS把全角转换成半角(只允许输入数字、小数点与负号)
<input
onkeypress="var k=event.keyCode; return k>=48&&k<=57||k==46||k==45"
onpaste="return !clipboardData.getData('text').match(//D/)"
ondragenter="return false" style="ime-mode:Disabled"
>
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四、用JS把全角转换成半角(只允许输入数字)
<input
onkeypress="var k=event.keyCode; return k>=48&&k<=57"
onpaste="return !clipboardData.getData('text').match(//D/)"
ondragenter="return false" style="ime-mode:Disabled"
>
五、不允许输入全角字符
<INPUT name="CardId" onKeyUp="quanjiao(this);">
<script language="javascript">
function quanjiao(obj)
{
var str=obj.value;
if (str.length>0)
{
for (var i = str.length-1; i >= 0; i--)
{
unicode=str.charCodeAt(i);
if (unicode>65280 && unicode<65375)
{
alert("不能输入全角字符,请输入半角字符");
obj.value=str.substr(0,i);
}
}
}
}
</script>