ASP.NET 자바스크립트를 이용한 FileUpload 확장자 검사

자바스크립트

function checkFileExtension(elem) {
    var filePath = elem.value;

    if(filePath.indexOf('.') == -1)
        return false;
        
    var validExtensions = new Array();
    var ext = filePath.substring(filePath.lastIndexOf('.') + 1).toLowerCase();
    
    validExtensions[0] = 'jpg';
    validExtensions[1] = 'jpeg';
    validExtensions[2] = 'bmp';
    validExtensions[3] = 'png';
    validExtensions[4] = 'gif';  
    validExtensions[5] = 'tif';  
    validExtensions[6] = 'tiff';
    validExtensions[7] = 'txt';
    validExtensions[8] = 'doc';
    validExtensions[9] = 'xls';
    validExtensions[10] = 'pdf';
    
    for(var i = 0; i < validExtensions.length; i++) {
        if(ext == validExtensions[i])
            return true;
    }

    alert('The file extension ' + ext.toUpperCase() + ' is not allowed!');
    return false;
}

 

ASP.NET의 Page_Load에 다음 코드 추가

FileUpload1.Attributes.Add("onchange", "return checkFileExtension(this);");

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