Use PHP to realize three-level linkage in urban areas with attached database

Use php to realize three-level linkage in urban areas, can be made into a small plug-in form, and can be adjusted at any time if needed in the future

Let’s see how to do it

First write a p and then introduce the js package

The imported js file is named sanji.js

Then let’s take a look at how the js file is written

$(document).ready(function(e) {    
    //向p里面扔三个下拉
    var str = "";
    $("#sanji").html(str);
    
    FillSheng();
    FillShi();
    FillQu();//选中项变化    
    $("#sheng").change(function(){                
            FillShi();
            FillQu();
        })
    $("#shi").change(function(){
            FillQu();
        })
});//填充省的方法function FillSheng()
{    var pcode = "0001";       //父级代号    $.ajax({
            async:false,
            url:"chuli.php",
            data:{pcode:pcode},
            type:"POST",
            dataType:"TEXT",
            success: function(data){              //回调函数
                    var hang = data.split("|");    //根据行与行的分隔符来拆
                    var str = "";                    for(var i=0;i"+lie[1]+"";    //中间显示地区名称                    }
                    $("#sheng").html(str);        //把显示的地区名称填充进去                }
        });
}//填充市的方法function FillShi()
{    var pcode = $("#sheng").val();
    $.ajax({
            async:false,
            url:"chuli.php",
            data:{pcode:pcode},
            type:"POST",
            dataType:"TEXT",
            success: function(data){                    var hang = data.split("|");                    var str = "";                    for(var i=0;i"+lie[1]+"";
                    }
                    $("#shi").html(str);
                }
        });
}//填充区的方法function FillQu()
{    var pcode = $("#shi").val();
    $.ajax({
            url:"chuli.php",
            data:{pcode:pcode},
            type:"POST",
            dataType:"TEXT",
            success: function(data){                    var hang = data.split("|");                    var str = "";                    for(var i=0;i"+lie[1]+"";
                    }
                    $("#qu").html(str);
                }
        });
}

As long as one is written, the other two principles are the same as the above one

Let’s look at the processing page again. One processing page is used for three items

Take a look at the code that processes the page

StrQuery($sql);

The region table of the database is chinastates

Check all data based on the passed parent code

The final running effect is like this

## Let’s take a look at the contents of the database

There is a lot of content in the database, and the names of regions in the third-level linkage are all in it, using the code and sub-code method

Take Beijing for example. The code name of Beijing is 11, and the sub-code name of Beijing city below it is 11. The main code name of Beijing city is 1101, and the sub-code name of the region below Beijing city is 1101. When adjusting the region, you can query and it based on the main code number. The same sub-code number can be queried.

The above uses PHP to realize the simplest three-level linkage in urban areas, edited and organized by PHP Chinese website!

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