Day 3-student information management for JSP & servlet!

By the way to help the master to promote the original http://www.java1234.com/a/yuanchuang/ video tutorial, although not professional training structure, but fortunately explain delicate, easy to understand!

I have always thought that JSP & servlet is too simple and troublesome, so I only understand the operation, but I have never actually done anything. Later I went on to study the framework inexplicably. After my master's tutorial, I feel very benefited a lot ~ I feel totally different at once! Bunker ~~

I will copy some of the messy notes below, but I can understand it myself. Well, especially the paging submission of easyui, this is definitely a classic case.

Easyui paging submission
Current page

Number of records per page in rows

Select * from data table name limit start, size;
Start: from where it is displayed, page-1) * Rows can be obtained.
Size: number of records per page

Select count (*) as total from t_grade gets the alias for storing the number of records to total

Batch Delete

Delete from tablename (Table Name) where field in (1, 3, 6 );
// Field indicates the field name
// Delete the entry with field value 1 3 6

Firfox also supports breakpoint, type debug

Join method of the array: Convert the string into an array, which is automatically matched.

Jquery POST method

Four parameters: First: Submission path
Second: Submit Parameters
Third: callback Method
Fourth: Submitted data type

$. Post ("gradedelete", {delids: IDS}, function (result ){
If (result. Success ){
Alert ("deleted successfully! ");
} Else {
Alert ("deletion failed! ")
}
}, "JSON ");

Garbled information during asynchronous submission may be generated after submission
Request. setcharacterencoding ("UTF-8 ");

$ ("# S_sex"). ComboBox ('getvalue ')

Time query in MySQL, convert to days, and then query
"And to_days (S. Birthday)> = to_days ('" + beginbirthday + "')"

// Clear easyui
$ ("# Sex"). ComboBox ("setvalue ","");

Hidden uses the hidden field to hide the submitted Form

Remember to pay attention to the cascading deletion issue when associating tables.