Jquery ajax 学习笔记

时间：2023-03-09 03:14:44
Jquery ajax 学习笔记

本人的js & jq 一直是菜鸟级别,最近不忙就看了看ajax方面的知识,文中部分内容参考自这里&这里 之前一直用js写ajax现在基于jq实现方便多了~

$.get & $.post 和 $.ajax的区别

之前看过同事写过$.post,而我一直用$.ajax,后来才知道$.get()和$.post()都是通过get和post方式来进行异步,$.ajax()说是jquery最底层的ajax实现的,这里我们使用$.ajax的方式实现.

调用无参方法

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
//调用无参方法
$("#Button1").click(function () {
    $.ajax({
        //要用post方式     
        type: "Post",
        //方法所在页面和方法名     
        url: "About.aspx/SayHello",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (data) {
            //返回的数据用data.d获取内容     
            alert(data.d);
        },
        error: function (err) {
            alert("Error: " + err);
        }
    });
})
1
2
3
4
5
6
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static string SayHello()
{
    return "Hello Ajax!";
}

这里只列出常用的$.ajax的属性以及方法详情请参考这里

有点类似类似调用WebService,后台方法必须为static,访问范围为protect/public,

WebMethod特性是必须的,这样才能被客户端脚本调用,支持远程调用.

ScriptMethod特性是可选的,用于指定调用方法的 HTTP 谓词(GET 或 POST),以及指定输出格式(JSON或XML)没有此特性,方法则默认只能被HTTP POST方式调用,并且输出将序列化为 JSON.

Asp.net 3.5以上可直接使用以上两个命名空间,Asp.net 2.0需安装Asp.net Ajax,或者单独引用Asp.net Ajax的System.Web.Extensions.dll.

如后台方法无参数,data项可填为"{}"或者直接省略.Asp.net 3.5以上使用返回值,需要加上".d",如以上代码里的"data.d",Asp.net 2.0直接使用"data"就行了.原因可能是两者序列化的方法有所不同.

调用有参方法

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
//调用返回有参方法
$(function () {
    $("#Button2").click(function () {
        $.ajax({
            type: "Post",
            url: "About.aspx/Hello",
            //方法传参的写法一定要对，name为形参的名字,age为第二个形参的名字     
            data: "{'name':'chenxu','age':'21'}",
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (data) {
                //返回的数据用data.d获取内容     
                alert(data.d);
            },
            error: function (err) {
                alert("Error: " + err);
            }
        });
    });
});
1
2
3
4
5
6
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static string Hello(string name, string age)
{
    return string.Format("hello my name is {0}, {1} years old.", name, age);
}

调用返回集合方法

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
//调用返回集合方法
$("#Button3").click(function () {
    $.ajax({
        type: "Post",
        url: "About.aspx/GetList",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (data) {
            //插入前先清空ul     
            $("#list").html("");
            //递归获取数据     
            $(data.d).each(function () {
                //插入结果到li里面     
                $("#list").append("<li>" + this + "</li>");
            });
            alert(data.d);
        },
        error: function (err) {
            alert("Error: " + err);
        }
    });
});
1
2
3
4
5
6
7
8
9
10
11
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static List<string> GetList()
{
    List<string> list = new List<string>
    {
        "a","b","c","d","e","f"
    };
    return list;
}

调用返回实体方法

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
$("#Button4").click(function () {
    $.ajax({
        type: "Post",
        url: "About.aspx/GetPerson",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (data) {
            $(data.d).each(function () {
                alert(this["name"]);
            })
        },
        error: function (err) {
            alert("Error: " + err);
        }
    });
});
1
2
3
4
5
6
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static Person GetPerson()
{
    return new Person { name = "chenxu" };
}　　
1
2
3
4
public class Person
{
    public string name { get; set; }
}

调用返回DATASET

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
//调用返回DATASET方法
$('#Button5').click(function () {
    $.ajax({
        type: "POST",
        url: "WebService.asmx/GetDataSet",
        //data: "{}",
        dataType: 'xml', //返回的类型为XML
        success: function (result) { //成功时执行的方法
            //捕获处理过程中的异常并输出
            try {
                $(result).find("Table1").each(function () {
                    alert($(this).find("Id").text() + " " + $(this).find("Value").text());
                });
            }
            catch (e) {
                alert(e);
                return;
            }
        },
        error: function (result, status) { //出错时会执行这里的回调函数
            if (status == 'error') {
                alert(status);
            }
        }
    });
});
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
[WebMethod]
//[ScriptMethod(ResponseFormat = ResponseFormat.Xml)]
public static DataSet GetDataSet()
{
    DataSet ds = new DataSet();
    DataTable dt = new DataTable();
    dt.Columns.Add("ID", Type.GetType("System.String"));
    dt.Columns.Add("Value", Type.GetType("System.String"));
            
    DataRow dr = dt.NewRow();
    dr["ID"] = "1";
    dr["Value"] = ".NET";
    dt.Rows.Add(dr);
    dr = dt.NewRow();
    dr["ID"] = "2";
    dr["Value"] = "JAVA";
    dt.Rows.Add(dr);
    ds.Tables.Add(dt);
    return ds;
}

调用dataset总是出问题,之前记得这样写是好用的,找了好长时间没找到问题,哪位大神找到了告诉我.

把web form里面的方法GetDataSet放到web service(asmx)中 并设定 contentType: "text/xml; charset=utf-8",dataType: 'xml'

调用ASHX 一般处理程序

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
//调用ASHX 一般处理程序
$("#Button6").click(function () {
    $.ajax({
        type: "Post",
        url: "Hello.ashx",
        contentType: "application/json; charset=utf-8",
        dataType: "html", //此处需要写成html
        success: function (data) {
            alert(data);
        },
        error: function (err) {
            alert("Error: " + err);
        }
    });
});
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
/// <summary>
/// Hello 的摘要说明
/// </summary>
public class Hello : IHttpHandler
{
    public void ProcessRequest(HttpContext context)
    {
        context.Response.ContentType = "text/plain";
        context.Response.Write("Hello World");
        context.Response.End();
    }
    public bool IsReusable
    {
        get
        {
            return false;
        }
    }
}

完整code

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
<%@ Page Title="主页" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"
    CodeBehind="Default.aspx.cs" Inherits="JqueryAjax._Default" %>
<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
    <script src="Scripts/jquery-1.4.1.js" type="text/javascript"></script>
    <script type="text/javascript">
        $(function () {
            //调用无参方法
            $("#Button1").click(function () {
                $.ajax({
                    //要用post方式     
                    type: "Post",
                    //方法所在页面和方法名     
                    url: "About.aspx/SayHello",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (data) {
                        //返回的数据用data.d获取内容     
                        alert(data.d);
                    },
                    error: function (err) {
                        alert("Error: " + err);
                    }
                });
            })
            //调用返回有参方法
            $(function () {
                $("#Button2").click(function () {
                    $.ajax({
                        type: "Post",
                        url: "About.aspx/Hello",
                        //方法传参的写法一定要对，str为形参的名字,str2为第二个形参的名字     
                        data: "{'name':'chenxu','age':'21'}",
                        contentType: "application/json; charset=utf-8",
                        dataType: "json",
                        success: function (data) {
                            //返回的数据用data.d获取内容     
                            alert(data.d);
                        },
                        error: function (err) {
                            alert("Error: " + err);
                        }
                    });
                });
            });
            //调用返回集合方法
            $("#Button3").click(function () {
                $.ajax({
                    type: "Post",
                    url: "About.aspx/GetList",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (data) {
                        //插入前先清空ul     
                        $("#list").html("");
                        //递归获取数据     
                        $(data.d).each(function () {
                            //插入结果到li里面     
                            $("#list").append("<li>" + this + "</li>");
                        });
                        alert(data.d);
                    },
                    error: function (err) {
                        alert("Error: " + err);
                    }
                });
            });
            //调用返回实体方法
            $("#Button4").click(function () {
                $.ajax({
                    type: "Post",
                    url: "About.aspx/GetPerson",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (data) {
                        $(data.d).each(function () {
                            alert(this["name"]);
                        })
                    },
                    error: function (err) {
                        alert("Error: " + err);
                    }
                });
            });
            //调用返回DATASET方法
            $('#Button5').click(function () {
                $.ajax({
                    type: "POST",
                    url: "WebService.asmx/GetDataSet",
                    //data: "{}",
                    dataType: 'xml', //返回的类型为XML
                    success: function (result) { //成功时执行的方法
                        //捕获处理过程中的异常并输出
                        try {
                            $(result).find("Table1").each(function () {
                                alert($(this).find("Id").text() + " " + $(this).find("Value").text());
                            });
                        }
                        catch (e) {
                            alert(e);
                            return;
                        }
                    },
                    error: function (result, status) { //出错时会执行这里的回调函数
                        if (status == 'error') {
                            alert(status);
                        }
                    }
                });
            });
            //调用ASHX 一般处理程序
            $("#Button6").click(function () {
                $.ajax({
                    type: "Post",
                    url: "Hello.ashx",
                    contentType: "application/json; charset=utf-8",
                    dataType: "html", //此处需要写成html
                    success: function (data) {
                        alert(data);
                    },
                    error: function (err) {
                        alert("Error: " + err);
                    }
                });
            });
        })
    </script>
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
    <h2>
        ASP.NET Jquery Ajax 调用后台方法示例.
    </h2>
    <input id="Button1" type="button" value="调用无参方法" />
    <input id="Button2" type="button" value="调用有参方法" />
    <input id="Button3" type="button" value="调用返回集合方法" />
    <input id="Button4" type="button" value="调用返回实体方法" />
    <input id="Button5" type="button" value="调用返回DATASET方法" />
    <input id="Button6" type="button" value="调用ASHX" />
    <ul id="list">
    </ul>
</asp:Content>
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.Services;
using System.Web.Script.Services;
using System.Data;
namespace JqueryAjax
{
    public partial class About : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
        }
        [WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public static string SayHello()
        {
            return "Hello Ajax!";
        }
        [WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public static string Hello(string name, string age)
        {
            return string.Format("hello my name is {0}, {1} years old.", name, age);
        }
        [WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public static List<string> GetList()
        {
            List<string> list = new List<string>
    　　　　 {
        　　　　"a","b","c","d","e","f"
    　　　　 };
            return list;
        }
        [WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public static Person GetPerson()
        {
            return new Person { name = "chenxu" };
        }
    }
    public class Person
    {
        public string name { get; set; }
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
namespace JqueryAjax
{
    /// <summary>
    /// Hello 的摘要说明
    /// </summary>
    public class Hello : IHttpHandler
    {
        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            context.Response.Write("Hello World");
            context.Response.End();
        }
        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Data;
/// <summary>
///WebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
//若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。
// [System.Web.Script.Services.ScriptService]
public class WebService : System.Web.Services.WebService
{
    public WebService()
    {
    }
    [WebMethod]
    public DataSet GetDataSet()
    {
        DataSet ds = new DataSet();
        DataTable dt = new DataTable();
        dt.Columns.Add("Id", Type.GetType("System.String"));
        dt.Columns.Add("Vlues", Type.GetType("System.String"));
        DataRow dr = dt.NewRow();
        dr["Id"] = "小花";
        dr["Vlues"] = "aaaaaaaaa";
        dt.Rows.Add(dr);
        dr = dt.NewRow();
        dr["Id"] = "小兵";
        dr["Vlues"] = "bbbbbbbbb";
        dt.Rows.Add(dr);
        ds.Tables.Add(dt);
        return ds;
    }
}

总结

一开始对data.d的这个d不是很理解,感谢这篇文章的博主,相比较与aspx  ashx只能通过ProcessRequest方法进行输出而不能在内部写static method,如果想在ashx中使用session只要实现IRequiresSessionState接口即可,要不然获取到session会为null.

相关文章