JavaScript alphabet and digital double-precision digital verification

Three pages special effects letters and digital double-precision digital Verification Oh, you can enter the number of legitimacy verification, the last side of an example to illustrate.

Verify the range of the number size

function Check_num_value (obj_name,obj,minvalue,maxvalue) {
var reg =/^[0-9]+$/;
if (obj.value!= "" &&!reg.test (Obj.value)) {
Alert (obj_name+ ' can only enter numbers!) ');
Obj.value = "";
Obj.focus ();
return false;
}else if (minvalue>obj.value| | Obj.value>maxvalue) {
The scope of alert (obj_name+) is "+minvalue+"-"+maxvalue+");
Obj.value= "";
Obj.focus ();
return false;
}

}

Verification can only be letters and numbers

function Checkzmornum (zmnum) {
var zmnumreg=/^[0-9a-za-z]*$/;
if (zmnum.value!= "" &&!zmnumreg.test (Zmnum.value)) {
Alert ("Only enter letters or numbers, please re-enter http://www.111cn.net");
Zmnum.value= "";
Zmnum.focus ();
return false;
}
}

Verifying double digits

function Check_double (obj,obj_name) {
var reg =/^[0-9]+ (. [ 0-9]+)? $/;
if (obj.value!= "" &&!reg.test (Obj.value)) {
Alert (obj_name+ ' must be filled with a valid double number ');
Obj.value = "";
Obj.focus ();
return false;
}
}

Let's look at a simple example

<form name=form1 target= "_blank" method=post onsubmit= "return Dosubmit (This)"
Member number (6 digits): & Lt;input type=text name=mem_id>
<input type=submit name=submit1 value= "Submit"
</form>
< Script language= "javascript"
function Dosubmit (frm)
{
if (frm.mem_id.value.length!= 6)
{
Alert ( "Membership number must be 6");
return false;
}
Else
{
var mem_value = Frm.mem_id.value;
for (Var i=0; i<mem_value.length; i++)
{
if (mem _value.charat (i) < ' 0 ' | | Mem_value.charat (i) > ' 9 ')
{
Alert ("member numbers can only be numeric Http://www.111cn.net");
return false;
}
}
}
Frm.submit ();
return true;
}
</script>