Question

我尝试在Asp.Net中从FileUpload控件中选择一个文件时启动jQuery方法，但它不起作用。 jQuery方法必须检查所选的文件大小。我该如何解决这个问题？

<script type="text/javascript">
    function ValidateUploadButton() {
        //this code will be executed when a new file is selected
        $('#FileUpload1').bind('change', function () {
            //converts the file size from bytes to MB 
            var fileSize = this.files[0].size / 1024;

            //checks whether the file is less than 1 MB 
            if (fileSize > 1) {
                $('#errorMessage').html("The file is too big")
                alert("okey");
                //successfully validated 
            }
            else {
                alert("else");
            }
        });
    }
</script>

<asp:FileUpload ID="FileUpload1" runat="server" ClientValidationFunction="ValidateUploadButton" />
<span id="errorMessage"></span>

Answer 1

我将ClientValidationFunction属性更改为onchange。

<asp:FileUpload ID="FileUpload1" runat="server" onchange="ValidateUploadButton();" />
<span id="errorMessage"></span>

编辑脚本以删除＆＃39;更改＆＃39;现在绑定因为更改而调用了ValidateUploadButton。

<script type="text/javascript">
function ValidateUploadButton()
{
    //this code will be executed when a new file is selected
    //converts the file size from bytes to Ko 
    var fileSize = $('#FileUpload1')[0].files[0].size / 1024 / 1024;
    // USE THIS BELOW IF THE ONE ABOVE DOESN'T WORK
    //var fileSize = $('#<%= FileUpload1.ClientID %>')[0].files[0].size / 1024 / 1024;

    //checks whether the file is less than 1 MB 
    if (fileSize > 1)
    {
        $('#errorMessage').html("The file is too big")
        alert("okey");
        //successfully validated 
    }
    else
    {
        alert("else");
    }
}
</script>

修改

抱歉，我未能彻底测试。它现在应该工作。正确引用filesize的javascript语法是错误的。另外我添加了1024的额外除法，因此您将以MB而不是KB来获取它。

注意 - 这仅适用于一个文件，不支持多个文件。

使用Asp.Net控件启动jQuery方法

1 个答案: