ASP.NET -- WebForm -- 给图片添加水印标记

2018-11-20 03:20:37来源：博客园阅读 ()

ASP.NET -- WebForm: 给图片添加水印标记

ASP.NET：使用 WebForm(C#) 制作一个简单的为图片添加水印的页面。

1. Test2.aspx文件

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Test2.aspx.cs" Inherits="Test2" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:FileUpload ID="FileUpload1" runat="server" />
        <asp:Button ID="Button1" runat="server" Text="上传" onclick="Button1_Click" />
        &nbsp;&nbsp;&nbsp;&nbsp;水印文字：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:Button ID="Button2" runat="server" Text="添加水印" onclick="Button2_Click" /><br />
        <asp:Image ID="Image1" runat="server" />
        <asp:Image ID="Image2" runat="server" />
    </div>
    </form>
</body>
</html>

2. Test2.aspx.cs文件

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Drawing;

public partial class Test2 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        //上传图片并保存
        HttpPostedFile imgfile = Context.Request.Files[0];
        imgfile.SaveAs(Context.Request.MapPath("image/TestImg.jpg"));
        Image1.ImageUrl = "./image/TestImg.jpg";
    }


    protected void Button2_Click(object sender, EventArgs e)
    {
        //创建位图，位图来自image文件
        using (Bitmap map = (Bitmap)Bitmap.FromFile(Context.Request.MapPath("image/TestImg.jpg")))
        {
            using (Graphics g=Graphics.FromImage(map))
            {
                //画水印文字在位图上
                g.DrawString(TextBox1.Text, new Font("黑体", 14.0f, FontStyle.Bold), Brushes.Blue, new PointF(map.Width - 120, map.Height - 30));
                //将画好水印文字的位图保存
                map.Save(Context.Request.MapPath("image/TestImg2.jpg"));
            }
        }

        Image2.ImageUrl = "./image/TestImg2.jpg";
    }
}