Difference between RegisterStartupScript and RegisterClientScriptBlock
>
RegisterStartupScript will append the javascript code just above the closing
form tag.
> The javascript code will get executed only after complete rendering of the View.
> Hence if the javascript is based on any controls, the code will be executed without having any error.
> For example, if the javascript fetches value of any label on View, it will be readly available.
> The following code is used for appending the javascript code by using
RegisterStartupScript.

>
RegisterClientScriptBlock appends the javascript code just after the starting
form tag.
> Here javascript will be executed before the controls get rendered.
> Hence none of the controls will be available for the execution of the javascript.
> If the javascript code fetches any lable value, it will not be available.
> The following code is used for appending the javascript code by using
RegisterClientScriptBlock.
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