Asp.Net中验证控件简单分析-白红宇

为了实现验证，.net提供了一个javascript脚本，当我们生成一个asp.net页面时，通过查看页面源代码的方式，会发现都调用了下面一个javascript文件：

asp.net的大部分验证都是通过这个文件进行的，下面我就以一个最简单的必入项验证控件来说明一下：

第一步：

当进入页面时首先赋值：var Page_Validators = new Array(document.getElementById("RequiredFieldValidator1"));

然后会根据这个变量的值遍历进行验证，

接着调用ValidatorOnLoad方法，然后在这个方法中调用ValidatorHookupControlID，ValidatorHookupControl，ValidatorHookupEvent

最主要是在ValidatorHookupEvent中给控件加载事件

eval("control." + eventType + " = func;");

比如onblue，onkeypress，onchange等事件

接下来根据加载的事件当事件发生时调用对应的方法

第二步：

当用户输入时调用ValidatedTextBoxOnKeyPress，主要是用来判断用户是否输入了回车键，如果是的话触发验证

第三步：

当用户输入回车或者离开焦点时调用以下方法进行验证：

ValidatorOnChange，ValidatorValidate，IsValidationGroupMatch，RequiredFieldValidatorEvaluateIsValid，ValidatorGetValue，

ValidatorTrim，ValidatorUpdateDisplay，ValidatorUpdateIsValid，AllValidatorsValid

主要就是根据用户的输入进行判断，决定是否显示错误信息：val.style.display = val.isvalid ? "none" : "inline";

附修改后的带有一个必入项验证的页面源码(将WebResource.axd文件中相应的方法都移到本页面了)

DOCTYPE html PUBLIC

-//W3C//DTD XHTML 1.0 Transitional//EN

http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd

html xmlns

http://www.w3.org/1999/xhtml

head

title

无标题页

title

></

head

body

form

div

input type

hidden

name

__VIEWSTATE

value

/wEPDwULLTE5MDkxNzgwODFkZKLnaM8iGUsgGiWldhYd7fCPmt6s

div

input name

TextBox1

type

text

TextBox1

span id

RequiredFieldValidator1

style

color:Red;display:none;

RequiredFieldValidator

span

></

div

script type

text/javascript

<!--

页面加载时执行的方法

var Page_ValidationVer

125

;

var Page_IsValid

true

;

var Page_BlockSubmit

false

;

var Page_InvalidControlToBeFocused

null

;

function ValidatorOnLoad()

{

(

typeof

(Page_Validators)

undefined

)

return

;

var i, val;

for

; i

Page_Validators.length; i

)

{

val

Page_Validators[i];

(

typeof

(val.evaluationfunction)

string

)

{

eval(

val.evaluationfunction =

val.evaluationfunction

;

);

}

(

typeof

(val.isvalid)

string

)

{

(val.isvalid

False

)

{

val.isvalid

false

;

Page_IsValid

false

;

}

else

{

val.isvalid

true

;

}

else

{

val.isvalid

true

;

}

(

typeof

(val.enabled)

string

)

{

val.enabled

(val.enabled

False

);

}

(

typeof

(val.controltovalidate)

string

)

{

ValidatorHookupControlID(val.controltovalidate, val);

}

(

typeof

(val.controlhookup)

string

)

{

ValidatorHookupControlID(val.controlhookup, val);

}

Page_ValidationActive

true

;

}

function ValidatorHookupControlID(controlID, val)

{

(

typeof

(controlID)

string

)

{

return

;

}

var ctrl

document.getElementById(controlID);

((

typeof

(ctrl)

undefined

)

(ctrl

null

))

{

ValidatorHookupControl(ctrl, val);

}

else

{

val.isvalid

true

;

val.enabled

false

;

}

function ValidatorHookupControl(control, val)

{

(

typeof

(control.tagName)

string

)

{

return

;

}

(control.tagName

INPUT

control.tagName

TEXTAREA

control.tagName

SELECT

)

{

var i;

for

; i

control.childNodes.length; i

)

{

ValidatorHookupControl(control.childNodes[i], val);

}

return

;

}

else

{

(

typeof

(control.Validators)

undefined

)

{

control.Validators

new

Array;

var eventType;

(control.type

radio

)

{

eventType

onclick

;

}

else

{

eventType

onchange

;

(

typeof

(val.focusOnError)

string

val.focusOnError

)

{

ValidatorHookupEvent(control,

onblur

ValidatedControlOnBlur(event);

);

}

ValidatorHookupEvent(control, eventType,

ValidatorOnChange(event);

);

(control.type

text

control.type

password

control.type

file

)

{

ValidatorHookupEvent(control,

onkeypress

if (!ValidatedTextBoxOnKeyPress(event)) { event.cancelBubble = true; if (event.stopPropagation) event.stopPropagation(); return false; }

);

}

control.Validators[control.Validators.length]

val;

}

function ValidatorHookupEvent(control, eventType, functionPrefix)

{

var ev;

eval(

ev = control.

eventType

;

);

(

typeof

(ev)

function

)

{

ev.toString();

ev.substring(ev.indexOf(

{

)

, ev.lastIndexOf(

}

));

}

else

{

;

}

var func;

(navigator.appName.toLowerCase().indexOf(

explorer

)

{

func

new

Function(functionPrefix

ev);

}

else

{

func

new

Function(

event

, functionPrefix

ev);

}

eval(

control.

eventType

= func;

);

}

按键事件

function ValidatedTextBoxOnKeyPress(

event

)

{

(

event

.keyCode

)

{

ValidatorOnChange(

event

);

var vals;

((

typeof

(

event

.srcElement)

undefined

)

(

event

.srcElement

null

))

{

vals

event

.srcElement.Validators;

}

else

{

vals

event

.target.Validators;

}

return

AllValidatorsValid(vals);

}

return

true

;

}

离开焦点依次执行以下方法

function ValidatorOnChange(

event

)

{

(

event

)

{

event

window.

event

;

}

Page_InvalidControlToBeFocused

null

;

var targetedControl;

((

typeof

(

event

.srcElement)

undefined

)

(

event

.srcElement

null

))

{

targetedControl

event

.srcElement;

}

else

{

targetedControl

event

.target;

}

var vals;

(

typeof

(targetedControl.Validators)

undefined

)

{

vals

targetedControl.Validators;

}

else

{

(targetedControl.tagName.toLowerCase()

label

)

{

targetedControl

document.getElementById(targetedControl.htmlFor);

vals

targetedControl.Validators;

}

var i;

for

; i

vals.length; i

)

{

ValidatorValidate(vals[i],

null

event

);

}

ValidatorUpdateIsValid();

}

function ValidatorValidate(val, validationGroup,

event

)

{

val.isvalid

true

;

((

typeof

(val.enabled)

undefined

val.enabled

false

)

IsValidationGroupMatch(val, validationGroup))

{

(

typeof

(val.evaluationfunction)

function

)

{

val.isvalid

val.evaluationfunction(val);

(

val.isvalid

Page_InvalidControlToBeFocused

null

typeof

(val.focusOnError)

string

val.focusOnError

)

{

ValidatorSetFocus(val,

event

);

}

ValidatorUpdateDisplay(val);

}

function IsValidationGroupMatch(control, validationGroup)

{

((

typeof

(validationGroup)

undefined

)

(validationGroup

null

))

{

return

true

;

}

var controlGroup

;

(

typeof

(control.validationGroup)

string

)

{

controlGroup

control.validationGroup;

}

return

(controlGroup

validationGroup);

}

function RequiredFieldValidatorEvaluateIsValid(val)

{

return

(ValidatorTrim(ValidatorGetValue(val.controltovalidate))

ValidatorTrim(val.initialvalue))

}

function ValidatorGetValue(id)

{

var control;

control

document.getElementById(id);

(

typeof

(control.value)

string

)

{

return

control.value;

}

return

ValidatorGetValueRecursive(control);

}

function ValidatorTrim(s)

{

var m

s.match(

(\S

(\s

)

)\s

);

return

null

)

: m[

];

}

function ValidatorUpdateDisplay(val)

{

(

typeof

(val.display)

string

)

{

(val.display

None

)

{

return

;

}

(val.display

Dynamic

)

{

val.style.display

val.isvalid

none

inline

;

return

;

}

((navigator.userAgent.indexOf(

Mac

)

(navigator.userAgent.indexOf(

MSIE

)

))

{

val.style.display

inline

;

}

val.style.visibility

val.isvalid

hidden

visible

;

}

function ValidatorUpdateIsValid()

{

Page_IsValid

AllValidatorsValid(Page_Validators);

}

function AllValidatorsValid(validators)

{

((

typeof

(validators)

undefined

)

(validators

null

))

{

var i;

for

; i

validators.length; i

)

{

(

validators[i].isvalid)

{

return

false

;

}

return

true

;

}

var Page_Validators

new

Array(document.getElementById(

RequiredFieldValidator1

));

-->

script

script type

text/javascript

<!--

var RequiredFieldValidator1

document.all

document.all[

RequiredFieldValidator1

] : document.getElementById(

RequiredFieldValidator1

);

RequiredFieldValidator1.controltovalidate

TextBox1

;

RequiredFieldValidator1.errormessage

RequiredFieldValidator

;

RequiredFieldValidator1.display

Dynamic

;

RequiredFieldValidator1.evaluationfunction

RequiredFieldValidatorEvaluateIsValid

;

RequiredFieldValidator1.initialvalue

;

-->

script

div

input type

hidden

name

__EVENTVALIDATION

value

/wEWAgLl/7L9DwLs0bLrBmRIrZczy6wbyzMNEvjnHwL+7PHV

div

script type

text/javascript

<!--

var Page_ValidationActive

false

;

(

typeof

(ValidatorOnLoad)

function

)

{

ValidatorOnLoad();

}

-->

script

form

body

html

本文转自永春博客园博客，原文链接：

http://www.cnblogs.com/firstyi/archive/2007/03/28/691061.html

，如需转载请自行联系原作者