Question

有一些功能，文本框只接受来自条形码扫描仪的输入，并限制来自键盘的任何其他输入。

Answer 1

以下是限制键盘的输入..只需尝试连接条形码扫描仪并检查它是否有效..

 textBox.onkeypress = function(e) {
       e = e || window.event;
       var charCode = (typeof e.which == "number") ? e.which : e.keyCode;
       if (/\D/.test(String.fromCharCode(charCode))) {
           return false;
       }
    };

LIVE DEMO

对于字母数字

Chk this

LIVE DEMO

Answer 2

在http://www.deadosaurus.com/detect-a-usb-barcode-scanner-with-javascript

上查看

在链接中，我修改为在不符合10个字符长度标准时自动清除文本，这可以假设不符合10个字符长度标准=未从条形码扫描器输入。

我正在使用ASP.NET，下面是我的示例：

对于ASP代码：

<asp:TextBox ID="TextBoxComponentPartNumber" runat="server" onkeypress="AutoClearOrSetInputText(event,this.id);" ></asp:TextBox>
        <asp:TextBox ID="TextBoxAssemblyPartNumber" runat="server" onkeypress="AutoClearOrSetInputText(event,this.id);" ></asp:TextBox>

对于JavaScript：

<script type="text/javascript">

//This variables is for AutoClearOrSetInputText function
var pressed = false;
var chars = [];

//This function will auto clear or set input text box’s text value
function AutoClearOrSetInputText(eventForTextBox,idForTextBox) {

// add each entered char to the chars array
chars.push(String.fromCharCode(eventForTextBox.which));

// variable to ensure we wait to check the input we are receiving
if (pressed == false) {
// we set a timeout function that expires after 0.5 sec, once it does it clears out a list
// of characters
setTimeout(function() {
// check we have a long length e.g. it is a barcode
if (chars.length >= 10) {
// join the chars array to make a string of the barcode scanned
var barcode = chars.join(“”);
// assign value to input for barcode scanner scanned value
document.getElementById(idForTextBox).value = barcode;
}
else {
// clear value from input for non-barcode scanner scanned value
document.getElementById(idForTextBox).value = ”;
}
chars = [];
pressed = false;
}, 500);
}
// set press to true so we do not reenter the timeout function above
pressed = true;
}
</script>

仅允许从条形码扫描仪输入文本框并限制键盘的任何输入

2 个答案: