输入金额时处理

       处理长度，不允许其他字符 

       

      

function regInput(reg){
    if( reg == "") return false ;
    var srcElem = event.srcElement
    var oSel = document.selection.createRange()
    oSel = oSel.duplicate()
    oSel.text = ""
    var srcRange = srcElem.createTextRange()
    oSel.setEndPoint("StartToStart", srcRange)
    var num = oSel.text + String.fromCharCode(event.keyCode) + srcRange.text.substr(oSel.text.length)
    event.returnValue = reg.test(num)
}


 onkeypress="regInput(/^[0-9]{0,24}(\.?)[0-9]{0,2}$/)"