比较两个字符串在javascript中无法正常工作

Question

这是我的 Javascript 函数，我在其中比较两个字符串，一个值作为函数参数接收，另一个从来自 Spring 响应的 json 中获取。

但我很惊讶我无法将两个字符串与=== 和== 进行比较，我可以在调试器中看到值。

我正在通过我的 HTML 代码调用我的函数：

<textarea onblur="searchProduct(this.value)"></textarea >

Javascript：

function searchProduct(value)
{
    alert(value);
    for (i in allProducts) {
        console.log(allProducts[0].productName);
        var tempProductName=allProducts[i].productName;
            alert(tempProductName.toString() == value.toString());
        // checks product name is present or not
        if( tempProductName.toString() === value.toString()){
//          setting other values details of products
                    $('#description').val(allProducts[i].productDescription);
                    $('.cost').val(allProducts[i].unitPrice);
        }//if

        }
}//searchProduct

allProducts：春天的回应

[{"productId":3,"sku":"QTY","vendorProductId":"v1","productName":"P1name","productDescription":"p1 desc","supplierId":"s1 ","categoryId":"c","quantityPerUnit":1.0,"unitPrice":760.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0, "color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":148.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable": "N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted ":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":4,"sku":"QTY","vendorProductId":"v1","productName":"P2name", "productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0," availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":150.0,"unitsOnOrder":500.0,"reorderLevel" :150.0,"productAvailable":"Y","迪斯科untAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null ,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":5,"sku":"QTY","vendorProductId":"v1","productName":" P3name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize": 40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0, "reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"示例注释","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":6,"sku":"QTY ","vendorProductId":"v1","productName":"P4name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0," unitPrice":1.0,"msrp":1.0 ,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0," unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note ":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":7," sku":"QTY","vendorProductId":"v1","productName":"P5name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit ":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount": 0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL ":"图片路径","排名":10,"note":"示例注释","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null ,"idsku":"IDSKU1"},{"productId":8,"sku":"QTY","vendorProductId":"v1","productName":"P6name","productDescription":"p1 desc", "supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue", "size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y ","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate ":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":9,"sku":"QTY","vendorProductId":"v1","productName ":"P7name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0," availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder" :500.0,"reorderLevel":150.0,"productAvaila ble":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":" N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":10,"sku":"QTY","vendorProductId":" v1","productName":"P8name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp ":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock": 1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10 ,"note":"示例注释","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId": 11,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c" ,"quantityPerUnit":1.0,"unitPric e":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight" :1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1" },{"productId":12,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1", "categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color ":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N ","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":空，“麦芽酒rtExpiryDate":null,"idsku":"IDSKU1"},{"productId":13,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":" p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black ,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable ":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"示例备注","smsNotification":"N ","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":14,"sku":"QTY","vendorProductId":"v1 ","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp" :1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0 ,"unitsOnOrder":500.0,"reorderLevel": 150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","ranking":10,"note":"Sample Notes","smsNotification ":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":15,"sku":"QTY","vendorProductId ":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0 ,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0," unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"图片路径","排名":10,"note":"示例注释","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{" productId":16,"sku":"QTY","vendorProductId":"v1","productName":"P10name","productDescription":"p1 desc","supplierId":"s1","categoryId": "c","数量P erUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount" :0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0," pictureURL":"图片路径","ranking":10,"note":"示例备注","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null," idsku":"IDSKU1"}]

Answer 1

JS字符串比较是区分大小写的，你可能需要一个不区分大小写的，例如：

tempProductName.toUpperCase() === value.toUpperCase()

代替：

tempProductName.toString() === value.toString()

你不需要toString()，因为该字段已经是一个字符串。

Answer 2

查看您的代码，这应该可以工作。

尝试更改迭代器 - for..in 用于迭代对象（即字典）。要遍历数组，请使用常规 for 或 forEach：

function searchProduct(value) {
  allProducts
    .filter(function(product) {
      return product[productName] === value
    })
    .forEach(function(product) {
      $('#description').val(product.productDescription);
      $('.cost').val(product.unitPrice);
    });
}

Answer 3

您可以使用indexOf 和length 实现自己的字符串比较方法：

String.prototype.equals = function (str2) {
    return this.indexOf(str2) == 0 && this.length == str2.length;
}

或者更“PHP”风格的方法：

function string_compare (str1, str2) {
   return str1.indexOf(str2) == 0 && str1.length == str2.length;
}