怎么实现几个文本框中的值计算在另一个文本框中?下面是我的代码,错在哪了呢 ?
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this.l8.Text = (Convert.ToInt32(this.l1.Text) + Convert.ToInt32(this.l2.Text) + Convert.ToInt32(this.l3.Text) + Convert.ToInt32(this.l4.Text) + Convert.ToInt32(this.l5.Text) + Convert.ToInt32(this.l6.Text) + Convert.ToInt32(this.l7.Text)).ToString();