zoukankan      html  css  js  c++  java
  • js 调用后台,后台调用js

    <html xmlns="http://www.w3.org/1999/xhtml">
    <head id="Head1" runat="server">
    <title></title>
    <script src="JS/jquery.js" type="text/javascript"></script>
    <script type="text/javascript">
    $(function () {
    $("#btnTJ1").bind("click", function () {
    var result = '<% =Print2Web() %>';
    alert("执行完毕,请检查一下后台数据有没有打印出来");//结果显然没有打印出来
    });

    $("#btnTJ2").bind("click", function () {
    $("#<%= btnGet.ClientID %>").trigger("click");//效果实现了
    });
    });
    </script>
    </head>
    <body>
    <form runat="server">
    <input type="button" value="前台HTML元素调用后台方法" id="btnTJ1" />
    <input type="button" value="前台HTML元素调用后台事件" id="btnTJ2" />

    <div style=" visibility: hidden">
    <asp:Button ID="btnGet" runat="server" Text="辅助前台获取数据" onclick="btnGet_Click" />
    </div>
    </form>
    </body>
    </html>

    js 压缩图片

    <script type="text/javascript">
    $(document).ready(function () {
    var BH = $('.file-wrap img').height();
    function fileChange(e) {
    var f = e.files[0];
    var _size = f.size;
    if (_size > 2048 * 1024) {
    mui.alert('选择的图片超过限度,请重新选择!', '', function () { });
    return;
    }
    //console.log(f);
    var FR = new FileReader();
    FR.readAsDataURL(f);
    FR.onload = function (f) {
    compressImg(this.result, BH * 2, function (data) {
    //$("#newImg").attr("src",data);//保存图片压缩后的64位编码
    $('.file-wrap img').attr('src', data);
    });
    };
    }
    document.getElementById("image").addEventListener("change", function () {
    fileChange(this);
    }, false);
    function compressImg(imgData, maxHeight, onCompress) {
    if (!imgData) { return false };
    onCompress = onCompress || function () { };
    maxHeight = maxHeight || 100; //默认最大高度1000px
    var canvas = document.createElement('canvas');
    var img = new Image();
    img.src = imgData;

    img.onload = function () {
    if (img.height > maxHeight) {//按最大高度等比缩放
    img.width *= maxHeight / img.height;
    img.height = maxHeight;
    }
    var ctx = canvas.getContext("2d");
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    canvas.width = img.width;
    canvas.height = img.height;
    ctx.drawImage(img, 0, 0, img.width, img.height);
    onCompress(canvas.toDataURL("image/jpeg"));
    //console.log(canvas.toDataURL("image/jpeg"));
    $('#IMAGE_URL').val(canvas.toDataURL("image/

  • 相关阅读:
    从零开始学SQLSERVER-游标CURSOR(基础)
    从零开始学SQLSERVER-创建表
    从零开始学HTML-button
    从零开始学前端HTML-input标签
    专项测试实战 | 如何测试 App 流畅度(基于 FPS 和丢帧率)
    接口测试框架实战 | 流程封装与基于加密接口的测试用例设计
    软件测试之30分钟轻松搞定正则表达式基础
    Python 装饰器填坑指南 | 最常见的报错信息、原因和解决方案
    react16与react15之间的区别
    react-父子组件之间的交互传值
  • 原文地址:https://www.cnblogs.com/lp73/p/6475501.html
Copyright © 2011-2022 走看看