Javascript 在不丢失光标位置的情况下更新输入的值
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Updating an input's value without losing cursor position
提问by nice ass
I want to mandate that the value of a text box is lowercase using JavaScript. I've tried the code below, but the cursor jumps to the end of the input every time you press a key. How can I avoid this?
我想使用 JavaScript 强制文本框的值是小写的。我已经尝试了下面的代码，但是每次按下一个键时，光标都会跳到输入的末尾。我怎样才能避免这种情况？
$("#beLowerCase").keyup(function(){
$(this).val( $(this).val().toLowerCase() );
});
回答by nice ass
$("#beLowerCase").on('input', function(){
// store current positions in variables
var start = this.selectionStart,
end = this.selectionEnd;
this.value = this.value.toLowerCase();
// restore from variables...
this.setSelectionRange(start, end);
});
(fiddle)
（小提琴）
This actually works with CSS as well:
这实际上也适用于 CSS：
#beLowerCase{
text-transform:lowercase;
}
And server can take care of the actual lower-casing...
并且服务器可以处理实际的小写...
