如何在javascript上传之前验证图像的尺寸? [英] How to validate the dimensions of image before uploading it in javascript?
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问题描述
如果有任何解决方案可以验证图片尺寸,请在使用javascript进行上传之前告知我们。
我尝试了什么:
我在javascript中尝试了下面的代码,它正确地返回错误信息,但表格正在提交,尽管图像尺寸无效。
$(function(){
$(#btnSubmit)。bind(click,function(){
/ /获取FileUpload的引用。
var fileUpload = $(#fuLogo)[0];
//event.preventDefault();
if((fileUpload.value!= null& ;& fileUpload.value!=)||(document.getElementById(LogoDiv)。style.display ===none)){
//检查文件是否有效Image。
var regex = / ^(([a-zA-Z] :) |(\\ {2} \w +)\ $?)(\\(\\\ [\\\ 。] *))+(JPG | .JPG | .JPEG | .JPEG | .BMP | .BMP |巴纽| .PNG | .ICO | .ICO | .gif注意|。 GIF)$ /;
if(regex.test(fileUpload.value.toLowerCase())){
//检查是否支持HTML5。
if(typeof(fileUpload.files)!=undefined){
//启动FileReader对象。
var reader = new FileReader();
//读取图像文件的内容。
reader.readAsDataURL(fileUpload.files [0]);
reader.onload = function(e){
//启动JavaScript Image对象。
var image = new Image();
//设置从FileReader返回的Base64字符串作为源。
image.src = e.target.result;
image.onload = function(){
//确定高度和宽度。
var height = this.height;
var width = this.width;
if(height> 150 || width> 1500){
// alert(请上传包含有效尺寸的图片。);
//event.preventDefault();
document.getElementById(lblLogoMsg)。innerHTML =请上传有效尺寸的图片。;
//event.preventDefault();
返回false;
}
};
}
}
}
}
});
});
解决方案
(function(){
(#btnSubmit) .bind(click,function(){
//获取FileUpload的引用。
var fileUpload =
(#fuLogo)[0];
//event.preventDefault();
if((fileUpload.value!= null&& fileUpload.value!=)||(document.getElementById(LogoDiv)。style .display ===none)){
//检查文件是否有效Image。
var regex = / ^(([a-zA-Z] :) |(\\\ \\ {2} \w +)\
Please let me know if there is any solution to validate the image dimensions before uploading it in javascript.
What I have tried:
I have tried the below code in javascript which returns the error message correctly but the form is getting submitting despite the image dimensions are not valid.
$(function () { $("#btnSubmit").bind("click", function () { //Get reference of FileUpload. var fileUpload = $("#fuLogo")[0]; //event.preventDefault(); if ((fileUpload.value != null && fileUpload.value != "") ||(document.getElementById("LogoDiv").style.display==="none")) { //Check whether the file is valid Image. var regex = /^(([a-zA-Z]:)|(\\{2}\w+)\$?)(\\(\w[\w].*))+(.jpg|.JPG|.jpeg|.JPEG|.bmp|.BMP|.png|.PNG|.ico|.ICO|.gif|.GIF)$/; if (regex.test(fileUpload.value.toLowerCase())) { //Check whether HTML5 is supported. if (typeof (fileUpload.files) != "undefined") { //Initiate the FileReader object. var reader = new FileReader(); //Read the contents of Image File. reader.readAsDataURL(fileUpload.files[0]); reader.onload = function (e) { //Initiate the JavaScript Image object. var image = new Image(); //Set the Base64 string return from FileReader as source. image.src = e.target.result; image.onload = function () { //Determine the Height and Width. var height = this.height; var width = this.width; if (height > 150 || width > 1500) { //alert("Please upload image with valid dimensions."); //event.preventDefault(); document.getElementById("lblLogoMsg").innerHTML = "Please upload image with valid dimensions."; //event.preventDefault(); return false; } }; } } } } }); });
解决方案
(function () {
("#btnSubmit").bind("click", function () { //Get reference of FileUpload. var fileUpload =
("#fuLogo")[0]; //event.preventDefault(); if ((fileUpload.value != null && fileUpload.value != "") ||(document.getElementById("LogoDiv").style.display==="none")) { //Check whether the file is valid Image. var regex = /^(([a-zA-Z]:)|(\\{2}\w+)\
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