jQuery实现限制文本框的输入长度

//限制文本框的输入长度

$(function() {

 $(document).on("keypress",".txt-valid-len",function(e) {

 if(e.keyCode == 8) {

 returntrue;

 }

 else{

 varlen = $(this).data("maxlength") || 0;

 if(len > 0) {

 return(this.value.length <= len);

 }

 }

 returntrue;

 });

 //粘贴

 $(document).on("paste",".txt-valid-len",function() {

 varlen = $(this).data("maxlength") || 0;

 if(len > 0) {

 return((this.value.length + event.clipboardData.getData('Text').length) <= len);

 }

 returntrue;

 });

 $(document).on("keyup input",".txt-valid-len",function(e) {

 varkeyCode = e.keyCode || e.which || e.charCode;

 if(keyCode == 46 || keyCode == 8) {

 }

 else{

 varlen = $(this).data("maxlength") || 0;

 if(len > 0) {

 if(this.value.length > len) {

  this.value = com.cutStr(this.value, len,"");

 }

 }

 }

 });

});