Implementierungsmethode für Webform-Bildwasserzeichen und Bildüberprüfungscode, entwickelt von Asp.net

Beide müssen den Namespace einführen: using System.Drawing;

Backend Photoshuiyin.aspx.cs-Code:

<div>
<asp:FileUpload ID="FileUpload1" runat="server" />
<asp:Button ID="Button1" runat="server" Text="上传" /><br />
<asp:Image ID="Image1" runat="server" />
</div>

Effektanzeige:

protected void Page_Load(object sender, EventArgs e)
{
Button1.Click += Button1_Click;
}
void Button1_Click(object sender, EventArgs e)
{
//1、制作画布
System.Drawing.Image img = System.Drawing.Image.FromStream(FileUpload1.FileContent);
Graphics g = Graphics.FromImage(img);
//水印样式：画什么东西
string a = "http://www.itnba.com";
//字体、大小
Font f = new Font("黑体", 30);
//颜色
Brush b = new SolidBrush(Color.Red);
//0,0——开始画水印的位置
g.DrawString(a, f, b, 0, 0);
//保存路径
string path = "images/" + FileUpload1.FileName;
img.Save(Server.MapPath(path));
//在image控件中展示
Image1.ImageUrl = path;
}

2. Bildbestätigungscode

Front-End-Photoyanzhengma.aspx-Code:

Linkseite „YZM.aspx“ – Es ist kein Front-End-Code erforderlich, der Back-End-Code lautet:

<form id="form1" runat="server">
<div>
用户名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<br />
密码：<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
<br />
验证码：<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
<asp:Image ID="Image1" runat="server" ImageUrl="YZM.aspx" />
<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
<br />
<asp:Button ID="Button1" runat="server" Text="Button" />
</div>
</form>
</body>
</html>
<script type="text/javascript">
var aaa = 1;
document.getElementById("Image1").onclick = function () {
this.setAttribute("src", "YZM.aspx?id=" + aaa);
aaa++;
};
</script>