javascript - capture input and convert characters

此生再无相见时 提交于 2019-12-30 07:16:46

问题


I want to capture input charcters in text box, convert then according to a table and put them back in text box as user types.

<form id='myForm'>

Enter phone number:<input type="text" id='idMyText' name="myText" onKeyUp="alphaToNum(this.value)">
</form>




<script>
// on each keypress in input box, I want to capture key pressed,
// determine if key pressed belong to group of identified characters
// if, so then convert to specified numeric equivalent and return character 
// to text box.
// This mapping corresponds to numeric characters on blackberry device.
// Normally user has to press alt+letter to get numbers. This will provide
// quicker access to numeric characters on for numeric fields

function alphaToNum(e) {
 x = e;
 x = (x.replace(/W/, "1"));
 x = (x.replace(/E/, "2"));
 x = (x.replace(/R/, "3"));
 x = (x.replace(/S/, "4"));
 x = (x.replace(/D/, "5"));
 x = (x.replace(/F/, "6"));
 x = (x.replace(/Z/, "7"));
 x = (x.replace(/X/, "8"));
 x = (x.replace(/C/, "9")); 
 document.getElementById('idMyText').value = x; 
}

</script> 

回答1:


Should do the trick. Now works wherever caret is and even when you copy/paste WECZ into field (if that matters)

var conversionMap = {W:1,E:2,R:3,S:4,D:5,F:6,Z:7,X:8,C:9};
function alphaToNum(){
    var field = document.getElementById('idMyText');
    var value = field.value.split('');
    var i = 0, len = value.length;

    for(i;i<len;i++){
        if (conversionMap[value[i]]) {
            value[i] = conversionMap[value[i]];
        }
    }
    field.value = value.join('');
    // prevent memory leak.
    field = null;
}

** Edit after Tim Downs comment **




回答2:


It might be better to do this when the value changes in the input, rather than when the key is pressed. Otherwise, other forms of input (pasting value) will bypass this substitution.




回答3:


Should do the trick. Now works wherever caret is and even when you copy/paste WECZ into field (if that matters)

var conversionMap = {W:1,E:2,R:3,S:4,D:5,F:6,Z:7,X:8,C:9};
function alphaToNum(){
    var field = document.getElementById('idMyText');
    var value = field.value.split('');
    var i = 0, len = value.length;

    for(i;i<len;i++){
        if (conversionMap[value[i]]) {
            value[i] = conversionMap[value[i]];
        }
    }
    field.value = value.join('');
    // prevent memory leak.
    field = null;
}

its working good until we didn't use utf-8 chars like öéáí etc... any idea for repair this "leak" ?



来源:https://stackoverflow.com/questions/3873371/javascript-capture-input-and-convert-characters

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!